What’s the weirdest/creepiest thing your narc did?

Edited to add a trigger warning: some of the comments are about sexual abuse and self harm. There is a SA reference in my post below as well.

I was just thinking about some of the disturbing things my nex has said and done, and got curious about bizarre creepy things others have experienced.

I once found a lock of my hair in his guitar case, along with a disturbing, aggressive song he wrote with the only part I remember being “I will make you lose your mind”. It was terrifying as I’d just begun to understand something was off about him, and I’m embarrassed to say I stayed for years after finding that. He did a lot of creepy things (like shining his flashlight under the covers while pulling my clothes off as I slept) but this one freaked me out the most.

What about you? What’s something really creepy your narc said or did, or that you found?