Asian beauty items, specifically kbeauty and jbeauty skincare. I love hearing about people's skincare routines and new niche items, ingredients and brands. But my friends irl aren't really into beauty (everyone i know is so pragmatic lol).
I really love beauty empties- I used to follow subreddits related to finishing beauty products, aka panning them (panning meaning hitting the metal pan at the base of powder cosmetics; panning has come to generally mean using up your products). There is something so satisfying about using up your stuff and I like vicariously experiencing it through other people. I mentioned that I was saving my empties for a few months to review which ones were worth repurchasing and my friends laughed at me, thinking I was joking.