Personality
Kuroneko Satou shares many similar personality traits with the stereotypical magical girl, along with some of her own more unique downfalls. She is generally considered to be the good natured derpy big sister that loves everyone and who always smiles; whether she just won the lottery or fell down nine flights of stairs. But at the same time, Satou harbors personality traits that she herself hates-- childishness, selfishness, anger, jealousy, and greed. All traits that she is desperately trying to hide and make up for.
As a general rule of thumb, Satou is an optimist. Not because she always sees a glass as half full, since there are situations Satou can't find positive, but because she always looks for a way to fill it up again. Her optimism has the tendencies of combining with her stubborn will to create absolute stupidity; Satou's optimistic and naive beliefs are very hard to shake because she is so strongly convinced that she can find a way to turn any situation into a good one.
This is important to her character because it is what drives her through her otherwise angsty canon. No matter how many times reality slaps Satou in the face she finds a way to keep believing. And trust me; she gets slapped in the face a lot. She spends a good portion of her time tracking down and arresting magical criminals and sees a lot of suffering as a result, but always believes she can peacefully solve a problem. No matter how often she has failed in the past, Satou faces each following situation believing she can make it work. In this sense, she's a bit naive.
Her naive viewpoint is cast on people as well, so that she believes everyone can come to fit her idea of a "good person" if she treats them nicely enough. The golden rule of "treat others as you want to be treated" is very strongly embedded in her, and often misused. Satou would sooner try to help someone hurting her and treat them kindly than hurt them back, because she believes kindness can change people. Her canon reinforces and rejects her belief system, as Satou meets many people who change and many people who do not. The people who do change are what keep Satou motivated and the people who don't change just encourage her to "try harder next time".
It might be noted, however, that as her canon progresses she becomes more realistic about this belief. By the time point that I am pulling Satou from she is a bit quicker to stop befriending and start shooting. However, this applies only to criminals that are putting innocent lives at risk. When attempt normal social interactions she will continue to stubbornly try to change people with kindness.
Because by the way; Satou is friendly. She is always willing to extend her hand to a person and try to befriend them. Always. Once again, this goes back to her stubborn nature and how naive she is. Satou is very persistent when befriending, even with her enemies. When designing Satou, "LOVE" was one of the most important qualities that I was aiming to highlight. She has the Magical Girl sense of Love to an extreme; from the fact she believes ~kindness~ (&therefore love) can solve all problems to the fact that she is on en endless quest to befriend everything that moves.
Satou is also incapable of taking back love, an important thing to note because it leads to her being betrayed a lot. What this means is that if someone stops being her friend or does not talk to her for a long time she will contently wait and never change her feelings for them. It is illustrated most strongly in the case of Mikale Godono; he betrays Satou on numerous occasions and she welcomes him back as her friend everytime he has a change of heart. They play this game of being friends and being enemies for over four years before finally settling on friendship, and Satou's love for him only grows stronger during this time. She never once thinks to take any love back.
In a negative case, her own mother takes advantage of this fact to manipulate her daughter. Even when Satou learns that all of her suffering stems from her mother she cannot comprehend the idea of taking back all of the love she's built up for her parent. Horie uses and abuses this, knowing that nothing she can do will make Satou dislike her. Satou is so wrapped up in the idea of loving everyone that she turns it into a serious fault and allows it to almost control her. She has yet to reach a point where she understands it is okay to take back your love for someone, but by the end of her canon she forms a vague concept of it. Enough, at least, to stand up to those that are controlling her fate.
These traits help Satou to come off as a very kind and caring person. Which isn't a total lie either; Satou does honestly care about people's feelings. Remember how she's got ~love love power~ to the max? Her kindness makes her very sensitive to people's emotions and very, very paranoid about stepping on their toes. Satou tries to be really polite as a result and can come off as being a very timid person when you first meet her. This timid personality begins to fade as she becomes more comfortable around a person and learns how to not upset them.
She is so overly cautious of people that, when combined with her empathy, it becomes yet another fault. Her empathy is incredibly sensitive, to the point that her ability is referred to as "empathy sponging". Satou can occasionally confuse other peoples' feelings with her own and will act upon them as if they are hers; sometimes this means thinking she's in love but it can also lead her to join a murderer on his rampage. It doesn't help matters that Satou is also a moody teenager and has trouble dealing with her emotions without empathy. Her loving magical girl nature is the culprit behind this as it motivates her to pay such close attention to the feelings around her.
However, at the same time, Satou has selfish motives mixed in with her kindness. Because she is able to "sponge" and experience other people's feelings she puts a lot of effort into making them happy-- and not just for their sakes. Satou recognizes that she'll become sad if they are sad and does not want that. Similarly, when Satou is sad and can't think up a solution to her own problems she will spoil others and enjoy the temporary high she gets from their happiness. Satou tries to fool herself into believing her actions are motivated by honest kindness, but deep down she recognizes that she is just as selfish as she is kind. And this is something she is deeply ashamed of.
She tries to hold everyone to the same level of affection and has a hard time distinguishing between how you should love a friend compared to a family member or lover. Her love for her friends is sibling-like and her love for her sibling, Masume, is creepishly close to Siscon. Satou is very protective of those she cares about and can be considered a yanderekko, as she is not above cutting off a hand before it can hurt her friends.
Her character is meant to spin mostly around the concept of love, from the heart theme in her outfits to her heart-themed weapon, so it's important to note just how much of a driving force it is for her.
The love that is most commonly associated with Satou also has selfish lacing. Satou loves because she wants to be loved. She is willing to extend a hand to anyone because she really hopes they'll extend their hand back to her. Satou could be loved by a hundred people and she would still stubbornly chase person one hundred and one because she's never satisfied. This plays into the price of Satou's magic, which is the most important thing in the world to her; her existence. To Satou, nothing is more important than being acknowledged. Nothing means more to her than hearing people say that they like her and patting her head or praising her. To get that praise Satou was willing to throw her safety away and pursue a dangerous life of magic. She even dragged Masume with her, solely so she could be compared to Masume and surpass her and therefore get more praise. For that praise, Satou chases every opponent with the resolve to befriend them and for that acknowledgment she ends up living a hellish life. When things get bad then Satou can pull motivation from the idea that she might get praised for it. While a super hero is supposed to save the day just to be the good guy, Satou wants to save the day so that people will clap, cheer, and acknowledge her accomplishments.
And she hates that about herself.
At the core, Satou is super selfish. She absolutely hates it. For the first half of the "series" Satou completely denies the fact that she is selfish. She is written to be as pure-hearted as possible because that's the self image Satou wants to create. For the longest time Satou tells herself that she is not a bad person. She convinces herself that the price of her magic is "The People I Love" and that people forget her because losing them is the worst thing that could happen to her, when in reality the price of her magic is her own existence and her ability to be acknowledged and praised. By this point in her canon she has no choice but to accept the truth, but that will not stop her from trying to flower up her character.
The struggle between "the person I want to be" and "the person I am" plays a big role in her character, right next to love. Satou is a teenager and is struggling to figure out what type of person she wants to become as an adult. She is at "Point A" and desperately wants to reach "Point B" but has no idea how to accomplish that. So instead she pretends she has already reached "Point B" and sweeps "Point A" under the carpet.
... But enough of that, for now! We'll get back to it later. No really, we will!
So, kindness and love are huge characteristics of Satou's. So is intelligence... or perhaps a lack there of. When she was growing up, Satou(/Samantha at the time) loved to learn. Because she had fun learning but mostly because her parents praised her for it. She carried that same love for learning to Japan, but the praise ended. When Satou got to Japan she had trouble adjusting and was, for a short while, considered really dumb. Unfortunately, the few months of being an idiot had a greater impact on Satou than her childhood of being praised. Satou therefore has zero confidence in her intelligence and constantly belittles herself in regards to it.
Not all for no reason, though. She is kind of dumb. Satou's Japanese is a bit of a gag. She's always practicing it and carries Japanese words to the English speaking places she visits ( yes, she's Wapanese ). And she misuses a lot of phrases. If she were to speak Japanese, Satou would spam "desu" because she thinks it's polite and would use super formal vocabulary, even if that's actually really weird and awkward. Both because she's obsessed with manners and because she wants to seem smart.
Still on the note of intelligence, Satou misses out on a proper Jr High education. The price of her magic is being acknowledged and eventually all official record of her vanishes, which means she can't enroll in school. Even though she can't attend school officially she does try very hard to teach herself but self-teaching never makes up for a proper education. So Satou's knowledge is mostly practical; things she learns because she has to, like basic math, and misc. information she learns from reading and television. Satou will therefore struggle with more complicated math problems and isn't literature smart. She also never spends much time on creative things like art, fiction writing, and music and has elementary school talent in them.
Plus side? The girl's good at her sciences and history. She might be really modest about it, but Satou's gathered a lot of knowledge on these. Why? Because for a witch they are very practical. Her magic requires a lot of understanding of the world around her and Satou spends most of her life surrounded by magic. Later in her canon, Satou becomes an expert on her world's brand of magic because she's so obsessed with researching it!
... Still can't add taxes or do any trig, though, and will generally come off as a moron.
This selective knowledge is influenced by the fact that Satou is hard-working. She's also very stubborn. Once she decides to do something, it takes a lot of force to change her mind. This can be a good thing, as it helps her stay motivated with her self-teaching no matter how frustrating it is and is the reason why, in most of her battles, Satou finds a way to come out on top. She will not settle for less with herself and sets high standards, and though she will occasionally cry and get mopey and discouraged for periods of time, she is stubborn and determined enough to pull herself together and try again. Once again; she can see a glass as half empty but she will find a way to fill it up again.
However, it is also a strong fault in her. Largely because Satou does not know when to give up. She absolutely hates losing because she has a huge ego; the fact that she'd always pulled herself up again and found ways to end up on top in the past make Satou very reluctant to ever take second place now. And all for the selfish reason of her being very concerned with her pride and image.
Because yes, image and pride mean a lot to Satou. We're getting back to those things that she hates about herself and wants to hide. Pride plays a major factor in that idiotic smile too; Satou wants everyone to see her as a strong and dependable person. When she first moved to Japan with her parents, she was naturally teased a bit and failed a lot, and she resents this. Her parents went from being proud of her to being frustrated with how she couldn't adjust. Satou was very whiny and childish during this time, complaining about and hating her classmates, until her mother scolded it out of her, and is now set on never being that whiny and embarrassing girl again. So when she smiles, fights on, and treats people nicely, it's all because she wants to be liked and wants people to see her in a positive light. Her original motivation for becoming a good big sister to Masume was because she saw Masume as her rival. It felt good to the Satou of back then to have her rival so dependent on her and to be higher in status than they were. These feelings did eventually melt to honest love over the years, but it just goes to show how dark her heart can be.
As the heavy title she bears implies, Satou has a darker personality than she'd like. The witch of sins carries the weight of displaying many sins in her personality. As mentioned before, one of these is her pride, but Satou also displays some wrath, sloth, envy, gluttony, and greed. The only sin she can't comprehend enough to show off is lust, except in some situations, which will be explained.
Satou has some slight anger management problems. It's been mentioned before that she treats others nicely and stubbornly tries to "turn people good" with kindness, but Satou is only human; she can only go so long before getting at least a bit frustrated. In particular, Satou hates being wrong. But she also hates her temper. So, for as long as she can, Satou will grin and bear something that upsets her. When her temper does snap it really snaps. Satou will yell and scream and lash out with childish or troll-like verbal abuse, depending on how how her self control has been lost. Sometimes she will even react violently; as mentioned previous, Satou has some yandere tendencies that are a result of her combined love-love and angry angry sides.
Luckily, though she hates to be wrong, Satou can accept that she's wrong. In the case that you manage to convince her 100% that her argument is not logically sound she will just vent her anger by being a tsunderekko.
Sloth is yet another sin that Satou is guilty of. Obviously not because she's lazy, as it's been mentioned that Satou is a hard working person, but because of the times when she will give up. Though Satou is generally going to try to pull through all bad situations she will admit defeat on a couple things. Namely, Satou will drop any issue where she risks getting emotionally hurt. She's really afraid of that. It's sloth that keeps Satou from taking back love and only giving it. She's too scared of the pain and too lazy to try to find an alternate approach. Even if she's hardworking, Satou often finds herself drifting towards the solution that is easiest or least emotionally painful for her.
Satou is also tremendously guilty of envy. She wants to come out on top in everything and loves winning and getting praise, so seeing someone else get that praise and win makes her a bit bitter. Though she tries not to let it show, Satou is jealous of anyone who can cast a magic spell she can't or who does better in schoolwork than she does. Even if she can convince herself of a logical reason not to feel that way, the jealousy will always remain there. This was particularly true in the case of her little sister Masume, who was succeeding and getting praise while Satou was failing and being scolded. Her envy and pride are also the reasons Satou wanted magic in the first place; so that she could beat Masume in something.
Finally, greed. Satou isn't so much greedy with objects as she is with people. What was stated earlier about Satou trying to love people is no lie; she does try and she does end up with honest affection for a lot of people she meets. But her greed puts a nasty, almost yandere, spin on it. Satou hates losing people, whether it's because they stop liking her or are physically taken from her, and is severely protective. I'm mentioning her yandere tendencies again because they really aren't something to ignore. If people try to lay even one finger on those she cares about, Satou won't hesitant to snap that finger off their hand and shove it down their throat. She has a bit of a mama bear instinct towards her friends. This is especially true towards her little sister Masume; for all of the envy Satou feels towards her, she is even more protective of the little girl who naturally does everything Satou wants to do.
The issue of lust is not something Satou actively suffers from. Even though she enjoys being thought highly of and is conscious of how other people perceive her, Satou doesn't comprehend the idea of lust or really even understand love on any more level than what she feels for Masume. She actually builds an entire harem over the course of her canon but has a hard time evening comprehending the pure love her friends secretly harbor for her.
But that doesn't mean lust won't ever come up.
Satou has exceptionally strong empathy. She cares a lot about the people around her and therefore cannot always turn her empathy 'off' and ends up sharing their feelings. She's also a child/teenager and doesn't always comprehend what she feels in her heart, which means she has an equally hard time telling her feelings from what she senses with her empathy.
This is made worse by Satou's title-based ability; she was modified to be able to turn sins into "emotions" as well, and as a result convert them to magic. On one hand, this means Satou can create more magic from any other magic user... But at the same time, it means she can "absorb" the sins of people around her and accidentally act on them as if they were her own.
So though Satou herself doesn't suffer from lust, if she is around someone who does then she will begin acting on it. This usually ends with her comically chasing someone around to cuddle with them or kiss them. The cure for this is embarrassment, since that makes her tsun to protect her pride and forces her to stop focusing on the lust.
Satou also has a few running gags. She has a really weird concept of cute and likes collecting adorable things. She has also lost her sense of taste and cooks things with a flavor so strong that even she can taste them; combined with her love for sweet or spicy things, this results in meals most people cannot consume. She also watches a lot of Magical Girl shows and likes Mecha anime.