Ideas
i wanted to share that i experienced the same issue but without owning the Lovestruck pack, so this bug is not exclusive to that pack. in my case, the sim was a university npc (from Discover University world), not a default sim.
this npc had an animal ear hairstyle when first introduced. when they moved into my household, i removed that hairstyle from all outfits, and everything appeared fine at first. however, when the sim took a shower, the animal ear hairstyle returned while they were nude.
i fixed this by going into cas with the sim on their everyday outfit and pressing the plus to duplicate that entire appearance into a new slot. deleting the original outfit slot entirely. selecting a different hairstyle and confirming. then going back into cas again and choosing the hairstyle i wanted, then applying it. this method permanently resolved the issue. i believe the bug is related to how the game handles nude/outfit transitions, not specifically tied to Lovestruck. just wanted to share for others facing the same problem
I’ve seen this before and it’s not quite the exact same bug. Both equally annoying though.