Welp pack it up girls, he's been claimed. Nothing to be done about it now.
I actually do like Busujima for him. At this point in their relationship I think she kinda just gets him, which has transformed her hate boner for him into a regular boner. She makes a good foil for his bullshit and he for hers. Even if this goes nowhere it would be fun to see them date, at least for a while.