LET'S START ALPHABETICALLY (That's Aerrow, Haruka, Makoto, Oz, Shawn, Speed Racer and Virgil)
Aerrow
Sexuality: Asexual, no particular leaning.
Now, Aerrow is a very focused person by nature. Even when he is occasionally good-humoured and relaxed, he is never forgetful of the kind of person that he is. Which is a Sky Knight! And Aerrow's entire persona revolves around this ideal that he had been knighted with. As a result, a lot of other things get forgotten in his life. His room on the Condor is EXTREMELY bare compared to say, Finn's or Piper's, when confronted with the Oracle, he has no real "selfish" wish or desire. He simply wants his life to achieve a goal; the Sky Knight goal of defeating Cyclonia and winning.
So, how does that factor into his sexuality? For one, because of his intensity and focus on being a Sky Knight, Aerrow doesn't pay attention to hormones or social graces/standing. For him, they could very well not exist because they don't factor into being a Sky Knight! And because they don't, it's not important to him. That doesn't make Aerrow clueless, he's well aware of dating, love and concepts like that. It's simply when he's confronted with these concepts that he appears confused.
Will this ever change? Not unless canon josses me Possible, since his time in camp has made him more relaxed as a person, as Aerrow rather than Aerrow the Sky Knight.
Haruka
Sexuality: Asexual, no particular leaning
Haruka is a tengu. Yes, that needs to be stated up front because the whole of Tactics revolves around the clashing of Haruka's nature against the nature of the human world which he knows resides in and the nature of Kantarou. Now, tengus can have relationships. That's pretty much proven by Sugino and Muu-chan.
But Haruka personally doesn't care for relationships of a romantic. Haruka is analytic by nature. He notes down the pros and cons of whatever he sees, humans, youkai, etc. And one of the things he cannot see is any real pro or incentive for him to pursue a romantic relationship. It simply doesn't interest him in any way! That doesn't mean he can't be sexual. Haruka can or act sexual should he choose to (his gigolo routine comes to mind), but like I said earlier, there's no real benefit for him and he's not someone who gets lonely or actively seeks the company of others. Haruka is very much a loner and this enforces his need to keep his relationships strictly platonic.
Moving on from that point, Haruka's had BAD experiences with romance. He was sexually abused by his previous master Fuji and this clearly unhinged him to the point that when he sees Ayame (who resembles Fuji), his head begans to pound and he pretty much mouthrapes her. But there's no real pleasure in the act and he even says almost despairingly, "This is what you taught me to do, isn't it Fuji?" . His experiences with Fuji may be buried, but that doesn't mean he can't recall them. Sticking to platonic relationships and avoiding that kind of contact is more for Haruka's sanity level.
Makoto
Sexuality: Asexual, male-leaning
Anyone seeing a pattern here?
Now Makoto is no social butterfly. He keeps to himself, he doesn't come to school, he doesn't even get along with his own family and a great deal of his time is spent in his room, playing guitar. A lot of episodes, Makoto barely speaks at all, opting for a line or two at the most. This is where I talk mostly of people in Makoto's life and how they influence his sexuality. Note that the only two friends Makoto has ever had is Tarou (his cousin) and Masayuki. Tarou brings out mixed emotions on Makoto, mostly on the kidnapping, the suicide and Tarou's dead sister. They're not really repressed feelings as Makoto spends a great deal of time thinking about his father and his family.
No, it's Masayuki that really starts to change Makoto. Masayuki actually forces Makoto to react even if it's anger or plain annoyance, Masayuki gets under his skin. And because Masayuki is his only real link to other people, he causes Makoto to change his line of thinking. Makoto becomes more focused on personality and the way a person acts arounds others than gender. This is mostly due to the fact that Tarou and Masayuki defy his normal thinking of people. And once Makoto gets an idea in his head and once his mind is fixed, it's pretty hard to get him to wrap around anything new or different.
And this is why I said his sexuality is predominantly male-leaning. I'm basing this on two things. One, Makoto's mother hasn't really put women in a favourable light. Not that Makoto would judge every female to be his mother, but he would certainly think twice about it. It doesn't help that this stereotype is enforced by his grandmother who's ALSO terrible and made his life miserable and his servant who's no better. Like I said, Makoto isn't going to think of these reasons in actuality, but subconsciously, he doesn't have a huge amount of respect for womenkind (he calls his own mom "that woman" or "that female" and even when interacting with Kei, he's brasher and ruder than normal). Two, his most positive interactions have been male. His father is the most positive role model he has ever had. Masayuki is someone he dislikes, but still tolerates and willingly helps out. Tarou is the cousin he mafias for and Tarou is the one who occasionally calms him down. His most important relationships are with two males, which definitely puts a spin on the way he views people.
Oz
Sexuality: Bisexual, female-leaning
Oz loev girls. Oz loev lolis. Oz loev flirting with girls and he thinks they are wonderful, sweet things who need to be pampered and treated like princesses and so on. Oz is a romantic! Oz reads books on chivalry and courtship and he falls for it, hook, line and sinker. His feelings for the fairer sex are very straightforward, canon wise! Oz likes to woo, to ham it up, to make himself look wonderful and knightly. Oz is a dork. But what about the male sex? For one, Oz doesn't really care much. Sure, he would tease them if he felt it would be funny or if he wanted to cheer them up. He wouldn't really go overboard in the way he treats a man the way he treats a lady, but he would put on a few airs if he felt he needed to. But beyond that, Oz doesn't perceive himself to care much about males in any way.
This changes when Oz gets reverse-treatment. All of Oz's acting, his chivalric notions, etc is pretty much an act. Nothing more. He does sincerely believe that "Lady Sharon glows in the sunset with the fire of the west" but should someone tell him that "he is wonderful and charming", Oz would falter. Sharon takes his hand and Oz becomes a blushing wreck. When Alice corners him and touches him, Oz immediately flushes and flails and becomes the LEAST COHERENT PERSON ON EARTH. Even when his uncle hugs him, Oz is blushing and uneasy. So what does that mean?
For all of Oz's love and affectionate ways, Oz can't really understand affection towards himself. Of course, this ties into Oz's understand of his own self-worth and his beliefs over his existence. Oz simply cannot understand why anyone would be interested in him! He just doesn't understand it! He's willing to believe that every person out there is a shining jewel of beauty, but he is not. And that's why any kind of physical attraction/attention aimed at him causes him so much dismay and flailing. He can't comprehend it, so he blushes, he shies away or he flat out denies it. It takes him a while to truly grasp that it's not a bad thing, but this takes a long time for Oz to truly get and till then, he'll be Mister Denial.
Shawn
Sexuality: Pansexual
AHAHAHAHAHAHA OKAY.
Shawn loev girls.
Shawn loev guys.
What Shawn loev most?
A challenge. Shawn gets bored a little too quickly and easily. If you don't entertain him, he'll drop you like a hot potato on ice. It's that simple! Whether you're male or female doesn't really matter to him. He measure a person by their amusement value. As a result, Shawn has many crushes going on at the same time! Shawn has definite kinks in canon that also help him pick who he's interested in (like Shawn loves silky hair), so he doesn't hit on everyone. But if you keep him interested, then he wants you. Yes, you. It doesn't matter who you are, what you're like, whether you HATE SHAWN WITH A FIERY PASSION, Shawn will keep trying to bother you! He enjoys seeing people bumble and fluster and rage at him. It doesn't matter how many death threats he gets, he'll keep doing it! Nothing else means more to Shawn than to make sure life and people don't bore him to death.
(sob simplest sex essay for shawn ever)
Speed Racer
Sexuality: ....lolz brothersexual ASEXUAL
This essay is going to assume a lot since Speed's canon is horribly inconsistent at times.
SPEED ...has a people problem. He believes in everyone! He keeps believing in everyone! Even when someone betrays him, he keeps believing! And that, Racer X tells him once, is why he tends to get screwed over a lot. Okay, you say, I get that he's naive, but what does that mean?
It means that Speed knows nothing about how people are or react. He doesn't get that Trixie is head over heels in love with him. He doesn't understand why she keeps grabbing onto his arm. He certainly doesn't get the sunset dates they have. It's not because he's dumb, it's because Speed has a very, very different thinking on people. He's a lot like Aerrow in the sense he simply doesn't think it! He wants to race, be a racer, nothing more! So, for him, all girls are just friends, no matter how many times they fall for him and Trixie gets jealous, he simply won't understand because like Aerrow, it doesn't really factor into who he is. A racer! And that's where people take advantage. Speed is asexual. But he's also really pretty. So, very often, people in Speed's canon (Trixie included) try to get in on some Speed time. FORGET that he has no clue whatsoever, they still do it. Hell, Trixie calls herself his girlfriend and he still doesn't get it.
Does that mean there's nobody at all Speed would ever consider a relationship with? No. Even though Speed doesn't understand people very well, he does feel very strongly on them. He's a good guy who would like to help whoever he can! And should someone make a very strong impression on Speed, he becomes strongly attached to them, a very strong attachment that one can argue is alike to a crush. A good example is Racer X. Speed becomes obsessed with Racer X. He does incredibly reckless things (like racing on a stormy night, stealing Racer X's mask, etc) just to get closer to the man. When Racer X crashes, Speed STOPS HIS CAR and runs back to Racer X. Racer X has the most powerful effect on Speed throughout the entire show, to the point that when Racer X scolds him, Speed LITERALLY throws a tantrum and starts crying.
Long story short, Speed may be dumb on the way people think and act, but if you can impress him in some way, he'll be on your heels FOR A WHILE.
Virgil
Sexuality: Bisexual, female leaning
Once upon a time, KIDS WB introduced female love interests for Static/Virgil. One was Frieda! Virgil mentions in the first episode wanting to take her to the dance, but his nerve fails him and other things get in the way. You'd think next episode, he'd pick up where he left off. But he didn't! And Frieda's existence fell from love interest to amusing girl on the show. So then, they tried Daisy! Virgil had a definite interest in Daisy, one that was actually followed up for a grand total of...five episodes. In a show that had 52 episodes in total, this was something.
The problem here is Virgil's mentality is similar to Shawn's, though not as extreme. Virgil is about the shine and sparkle of something new and meetings girls, girls he can get along with or talk to, is something new to him (since Virgil wasn't the most popular kid in school, often getting bullied from time to time). But the problem is, Virgil moves on from one shiny topic to another. And the shiny topic of his life is being a superhero which not only takes away his time with girls or developing any relationships with girls, but it also causes his interest in them to wane considerably. After all, it's hard to care about a relationship when you have to defeat the Bang-baby of the day. So, as a result, he shunts his own interest in girls, leaving them rejected and annoyed (literally). Virgil just doesn't have the time or energy to devote to his hormones anymore.
So, has Virgil had any consistent relationships at all?
Sure.
There's Richie. Richie who will get his own essay at some point because talking about Richie IS AN ESSAY. But to sum it up, Static Shock's primary focus is not really Virgil but Virgil and Richie. You can even see that in the opening, where Richie is waiting for Virgil to show up at school and they do the dorky handshake. Suffice to say, Virgil can maintain a relationship if he really put his mind to it, but Frieda and Daisy (or any other girl for that matter) have been unable to make him interested or invested enough in wanting a stronger relationship in any way. Unlike Richie, whose friendship Virgil regards very highly.
Basically, in a nutshell, it takes a long time for someone to truly have a relationship (that's not platonic or deep) with Virgil and it requires a lot of energy from Virgil and the other person involved, or it doesn't work.
I WELCOME ANY THOUGHTS HERE I'm kinda braindead.