What is a hobby you enjoy, but seems too quirky or obscure to bring up in most conversations?

I'm not into Gundam but I know of it. I was surprised when my boss and like 3 other coworkers, when we all started on a new team,l and didn't know each other, started talking about their gunplas.

I came here to say this. Trying to fully explain usually leads to confusion, so I just simplify it and say they’re plastic models kits.