My sister and I are both in our 20s and still live at home with parents, neither of us are in the financial position to move out. We both pay rent/keep. All 4 of us (5 with the boyfriend included) all share a single bathroom, which means in the morning it's already like a military operation to ensure that there is enough time to get in the bathroom before we all start work. However, with her boyfriend staying it's another person that needs to get in there and he ends up using my 'slot' which means I have to get up earlier at 5:45am.
Her boyfriend stays over every week night as he lives further out from his job, so by staying he shaves off 40 minutes of his commuter.
AIBU to think 5 adults trying to get in the bathroom before 8am is too many?