All the LIs have a daily RNG check if they're horny. The chance seems to vary between LIS, a few are essentially always horny. If you have special pastries, giving them one makes them horny right away; you still have to ask for sex again.I've returned to the game after a long break, and I'm still having the same problem: I can't get sex from Erevi. I remember someone telling me how to fix this, but I can't remember the exact method. Can you help me?
Even if horny most still won't bump uglies unless their Affection is high enough. Giving them gifts is the straightforward way to boost it. You can also use Awe on them if you've progressed the vampires storyline far enough.
Erevi's storyline pretty much ensures her Affection is high enough once you knock her up the first time, but to get there you need to bring her sacrifices (bigger is better). And also agree to be her apprentice, of course. Where are you in her storyline?
Just checking, did you install any mods or edit files? Both can regularly bork the game. (The Spicy and Gnomes mods/patches are safe to install.)