Sex w my boyfriend

Okay I want to try something new with him we have sex quite a lot but our sex is GREAT but just want to spice things up a lil I have a fascination with Butts n me having on a strap on but I don't know how he would feel about this I love rubbing his butt and squeezing it and I like getting behind him n masterbating his penis for him this stuff turns me on , but I want try anal sex but it hurts to even try put it in. I like for him to rub it on my anal hole. I just want to know some new positions or new kinky things I can try.