Anal sex

So my best friend and I are a thing.. Kind of like friends with benefits. We have dated in the past and we absolutely love each other. One of he big things that he is into is anal when we are having sex because it's tighter than the vagina around his dick so it feels more pleasurable. we have tried doing that a couple of times and I've stopped him from doing it all but once because I felt really bad. So the thing I am asking is what are methods (or cheap things that minors could get to make anal sex more pleasurable for the girl or both?