Angels! Conflict! Shifting affiliations! Possible nepotism!
Something else I was just thinking about: if Damon hadn’t been born gay, he’d still be almost exactly the same vain, volatile character…just with a “Well, LADIES, how lucky FOR YOU that I’m asking you out” thing going on, maybe a little like Archie’s pal Reggie, or Beauty & The Beast’s Gaston. It worked out pretty ok for him that he was, though — for one thing, less cognitive dissonance involved in fantasizing about making out with himself.