[So many of the bad ends so far have been so quiet. It's eerie, I tell you!
Have one who probably isn't going to stop alternatively muttering things madly and screaming his head off in pain any time soon, to the point where he probably will have no voice by the end of the week. As it is, the Sphere (which he hasn't noticed) turns on just after one of the bouts of intense pain, and he's breathing slightly heavily.
...Also he seems to be chained to the wall or something, or at least carrying himself as though he were.]
This... This pain is nothing, compared to what it did to her...
[He dryly laughs once.] But as long as there's pain to be felt, that means I can still feel it. As long as I can still feel something, it hasn't gotten me completely.
[And then he laughs a little bit more, bitterly this time. After all, a whole lot of good that does in this situation.]
[...Yeah... What happened in his bad end, you may ask? Well, this bad end takes place shortly after his next meeting with the Tenjoin Asuka of his world. (He hopes to either visit her or have her visit him over the winter. That... probably isn't going to have the chance to actually happen, but he doesn't know that.) The Light of Ruin reappears in its true form at that time, kills Asuka, destroys her soul (so that she can't attempt to re-take her body or even come back as a ghost), and takes her body as its own. Why does it want her, a relatively powerless human? Because with her popularity, it will be able to use her music to obtain new followers, perhaps even some that control such things as nuclear missiles, or laser satellites. At the very least, it will be able to spark war.
Obviously, Manjoume tried to stop this from happening, but this time, he failed. He lost the duel. But the Light decided not to do the same to him and turn him into a permanent non-questioning follower immediately. Oh no - it decided to have a little fun first, in order to make Manjoume suffer for its defeat at Duel Academy. After all, Judai and anyone else who could possibly stand against it are also dead - what's the harm in a little torture?
So. He's been restrained and infected with the Light's energy. Not enough to completely control him immediately, but enough to cause him pain and drive him mad. He can't see or hear his spirits anymore (and the Ojamas may or may not be dead anyway, he doesn't know), his cards look like blank white pieces of cardboard, and he's slowly being driven mad via pain and the Light's power... with the knowledge that this is being purposefully drawn out and that when it is finally over, he'll be just like Asuka is. His soul destroyed, his body a blank slave of the Light, and not a thing he can do about it.
You can kick this guy down and he'll keep trying to get up again if he can, but it's kind of hard to get back up when you're chained to the ground. And there's only so much despair the average human can take.]