Because a sexy anti-hero is unheard of in the MC...OH WAIT THERE'S LOKI.
So yea, basically, Emma should be the X-Men's Loki, if we want to torture the metaphor even more.
Though yes, marketing to kids might be...problematic?
But I say a) not everything has to be marketed to kids and b) I dunno. Some kids might benefit from some upfront education about sex.