Curious

My boyfriend of over 10 + years has been asking me to put my dildo in his butt.We are in our mid 20's and I am open to new ideas. He loves anal. I have used my dildo on him once. He had asked me to do it again. I am not at all shy of his butt. I would love to strap one on and have at him!Last night while we were having sex. he came with out an orgasm. We had sex so long that I am hurting today. He went in the living room to watch T.V (porn)And I fell asleep and about 3 hours later I went in there and he was using the dildo on himself??He thought he heard me and jumped up really quick. To avoid the embarassment I hid in the corner and was kind of turned on watching him do his self in the butt??He is such a manly man. My best friend is gay and my man acts like if he hangs with him... he will be gay. I'm not sure how to react or what to think? I dont want to discourage him away from opening up to new ways to stimulate him. I am open for it? How do I initiate it? Should I? He also wants me to lick his butt.... I'm not very comfortable with that? Maybe if he shaved like me? Still them I think that is... not for me. I let him do anyhting to me.. i just want to satisfy him and I am a lil concerned and confused? Is it normal for a straight guy to like it in the butt?