The anal orgasm is more intense than ejaculation, maybe the bottom has not experienced such an orgasm before but I'm sure he's not hurt. When I was experimenting on my hole trying to get an anal orgasm it was too much for me and I couldn't continue to a full orgasm because it was overwhelming and I'm not used to it. But I'm sure with time I will be able to enjoy it.
Im a real bottom, feeling that dick opening up my hole gets me started working it in the way I what and then fucking me the way I want hitting my spot makes me a real cock loving faggot, ill milk that load outta a top. I've made a guy cum back to back to back before pulling out!