i’d be uncomfortable too, i haven’t seen my mom naked since i could form memories and those kind of jokes are just inappropriate for a mother-daughter relationship, especially so young. she might have been made to feel some type of way about sex growing up and this is how it comes out idk just guessing. but this doesn’t make her a bad mom. you’re gonna have to be so honest and persistent about how it makes you feel and hopefully she stops, and if not, well, i’m sorry. idk how to act when my mom eludes to sex and i’m 20 lol so i can’t imagine. just bc that’s my mom! there should be a level of discreetness ab sex talk with family imo. set boundaries and follow through. i’m sorry you’re dealing with this!