Bisexual flatmate
Q: If a female flatmate comes out as bisexual does one need to cover in front of her?
The default ruling is that a woman does not need to cover in front of another woman. Some schools said that a Muslim woman should cover in front of a non-Muslim woman due to the fear of her appearance that is normally covered being spoken about and revealed.
In this situation, I don’t see any need to do so unless she fears that some fitnah (sexual temptation) will occur by not doing so but I would advise against spending time alone with her as much as possible.