Probably just ask about it. They could be asexual. Years ago I was with someone who was, and we had sex, a lot of dirty fun, she was totally into it, but she didn’t cum and told me she doesn’t need to. I found out after that she loves having sex just to feel close and connect, not for sexual gratification, she didn’t masturbate either.
https://en.m.wikipedia.org/wiki/Gray_asexuality
Without knowing your relationship history, maybe your partner is somewhere in this space but doesn’t openly talk about it?
Nothing anymore. But from age 18 to mid 30s I kept my busted up old guitar pick in my wallet.
It had seen way too many shows, and it was brittle as hell. It’s in a shoebox with since other memories now.
Less unique, I carried around phenergan pills in my pocket for about 10 years. I’d had an episode of an unknown something setting off a reaction with my throat closing up. Urgent care gave me the pills when I left the hospital and I couldn’t not take them everywhere with me for a long time.