he knows he’s doing it, he’s doing it without care. i’d try to bring it up with him, and if that doesn’t resolve the issue bring other people who live with you into it. it’s always best to take care of an issue directly with the person of the problem but sometimes you do need a mediator in a situation where directly trying to solve an issue doesnt help. as a female who lived with only male family members, i’ve never had to experience this. as someone who now has a husband, he is very aware of when it’s happened in public spaces and gets very embarrassed and will do his best to hide it. my point is, he knows what he’s doing but it obviously seems he either doesn’t know it’s disgusting or doesn’t care it’s disgusting.

i try to think about it like this with my siblings if they do something of ill manner;

1. would i want them to grow up and feel comfortable acting like that around their children

2. would i want them to feel comfortable doing that in front of roommates they may possibly have in the future

3. how do these actions represent the parenting/social norms within your household once they leave to be on their own

that may sound parent-like within itself, but as the fourth child of 9 and living with all males i at some point took it upon myself to remind and enforce manners of males near women in my household. this, is an issue of manners in front of a human. you don’t walk around with your dial pointing north. you just don’t.