There's nothing. Minimum lust increases through
several methods but all of them except Omnibus's Gift are very straightforward about it. A Hot Blooded Nymphomaniac bimbo who took one of the Omnibus's Gift options and got two Crimstone piercings would hit min lust 80, and at that point it's really your own fault.
And yes, you can actually make yourself completely unable to play the game by getting your min lust up to 100 while not either having erectile dysfunction or being a centaur with a cock that's smaller than an Xbox. If you can't get it up, then you can walk around with 100 Lust, though you'll still lose every fight instantly.
In general minimum lust of 30 is nice so you're always primed for sex, while anything above that is actively harmful unless you're using black magic and anything above 50 is harmful even for black mages.