I'd keep it impersonal and put mentions of it with words that aren't associated with sex normally or are negatively associated with sex.

"Sex is nifty" is good in that it doesn't associate you with the sex, so doesn't illicit mental images. Nifty is also an odd word to associate with sex.

"I don't have a religious view on sex" is also unlikely to get the pervs going. Both of these are a bit boring through.

Failing that, to keep it more light hearted you might want to try adding in some sexual double entendres? Hard to balance the right level of subtlety and understandability though.