He’s right to feel uncomfortable because it’s inappropriate. My kids are 19 and 21 and while I am hopeful/happy for them to have intimate adult relationships they find fulfilling I don’t have any interest in those relationships happening under my roof with what is essentially a stranger. My son has been in a relationship with a nice young woman for about a year and a half and while I would have no issue with them sharing a room I wouldn’t want my 19 year old sharing her room with a freshly found boyfriend or vice versa, it is intimate and I care about the quality of my kids relationships and if they’re dating someone who doesn’t respect that I don’t want causal sex going on in my house I don’t know how quality this person they’re dating even is… for me, as the parent in this situation is that this feels way too much like casual sex which I feel isn’t in most people’s best interests. Hook up else where and figure it out six months down the road