The designers should decide for themselves and anyone should be able to play it.
I often think people underestimate the sexuality of youngsters, they want ignore that fact and block it out. An 11 year old can be just as sexually minded as a 15 year old depending on their level of puberty, I certainly was at that age. I sound very Sigmund Freud right now but younger kids are always obsessed with their rude bits.
Society hasn't sexualised anything more than it already was in my opinion, there's always been an ongoing theme of complaining middle aged people however.
Violence is fine in game form, I hate war IRL but in the video game world it doesn't phase me whatsoever since no-one's getting hurt.
As long as sex and violence are not merged the designers should put as much or as little in their games as they like.
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What film do atheists watch on Christmas?
Coincidence on 34th street.