Ah, I didn't mean (at least consciously) sexual urges exclusively. It's a more general impotency than that.
Your phrasing is interesting. I don't see the problem of overeating or a craving for chocolate as anything like the sex drive. The first two are mostly unconscious; you may try to overeat or find chocolate without realizing. But my sex drive is much stronger; it's difficult to be unaware of it, and it absorbs my conscious thinking into it. That I consider demonic, in the sense of something close to experiencing divinity.
Anyway, thanks for the recommendation. I'm heading to bed, but will begin reading it when I wake up.