Used to a friend of one of Jaiden's previous life's, who sacrificed himself in order to be a guardian spirit.
Somehow ended up as a possessed trading card that would kill people who were hurting Jaiden. Kaiba corp then send it into space where it was exposed to space magic that turned it yandere.
It then returned to earth with the expressed intend to murder everyone close to Jaiden so they could have him all to themselves (also torture him to show their affection).
Jaiden ended up fusing with them and now their his stand.>>108304258>He was fighting the literal Darkness in S4
And it was forgetable as fuck.