Yuu-Mi, Anime and the Apocalypse

Yuu-Mi was once the greatest hero alive until he died a tragic death. For the first time ever, he was killed in a match. The rules stated that the loser had to delete their character, thus he did. Except when his character got deleted so did Yuu-Mi.

Basically about a guy who dies and ends up in an apocalyptic world where he can summon anime characters.