One of the negative quirks a character can have gives them a chance to "molest" an ally when their Lust is high enough, forgot the name. Frisky?
not sure if Celezte was asking on how to get rid of arousal, molest will make it raise on another girl, maybe causing an affliction
there is a skill for maids, massage than can lower from a selected girl, with a drawback to them in a lower amount, as they have maid belt equiped that should not be much a trouble, also mages can have a cursed weapon, magic wand that does the same (but have no gear protection against its drawback)
also out of combat, on your supplies list, can bring both items to raise or lower lust, very handy when have some goals to receive lust damage or end dungeon with more than 60 for example (to unlock some cursed items)