It wasn't just Macauley Culkin trying to expand his acting horizons in 'Party Monster' (and then probably wishing he hadn't bothered). Seth Green was in on the act as well. In Green's case he played the part of James St James, the cross-dressing member of the so-called 'Club Kids' who went on to become a writer and 'famous for being famous' celebrity years after the club scene he was part of ended.
It was St James who wrote the original book 'Disco Bloodbath' upon which 'Party Monster' was based. Green, straight in real life but also known for being clean-cut, was always a strange choice to play him on screen. If nothing else, he managed to look fantastic in the costumes, and he's since gone on to have a fantastic career as a producer and director, as well as lending his voice to Chris Griffin on 'Family Guy.'