If it's not lying, then it's completely misunderstanding why including open, unmarked spoilers in a character bio is a bad thing. Not everyone who might want to watch it has seen Madoka Magica, and in Kyouko's case writing her whole backstory would spoil the entire series no matter what I did.

It's for the sake of the players, not to avoid metagaming.

In any case, I was addressing the reasoning behind the shortness of one of my character's histories. Refuting your downright insulting accusation is something appropriate for a co-GM to do.