Why do Christians hate sex?
That was linked to the Hellenes’ dread of loss of control. For them, ANY form of emotional outflow (which sex would classify as) was to be shunned, for such would probably result in one’s spiritual perfection getting loused up (read: torn asunder by the emotions’ rampage). Now consider that the zenith of said spiritual perfection was, in many cases, supposed to be transfiguration to a purely spiritual entity. This actually lay at the heart of some 19th-century misogyny, I understand–women and their sexual allure were inciting lust in men, and thus frustrating their ascendancy! (Now they get to explain what was frustrating women in that ascendancy…) Of course, I don’t think present-day erotophobia is going to match groups like the 12th-century Catharists, who completely interdicted sex (although there, the idea was to avoid binding more souls to this irredeemably corrupt world).