I have a really tight/small asshole and I want to try anal with my partner really bad, and he wants to try it real bad too, but everytime he tries to put his dick in my butt, it literally cannot enter, even with tons of lube, and he says that it hurts. I was wondering, is there a way to maybe “stretch” my ass, or anything else I can do so that I can take my partner in without causing him pain ?