My SO wants me to peg him

I’m not comfortable at all and when he asks for it (usually in the heat of the moment) I get so turned off. I love him and want him to feel sexually satisfied...I don’t like being that dominant and possibly tearing /hurting someone. He’s not asked in a serious discussion just when he is kinky and talks dirty. But I almost want to pleasure him in this way... we have a sex evening planned where we just enjoy each other for about 6hours, coming soon. Anyone been in this situation? I m adventurous but not super into this!!!

We are going on 3 years so still a new& young relationship