Butt stuff.. kinda

So my fiance lets me take our little vibrator and put pressure around his ass.. he moans all that.. idk y but I get turned on. Well the other day he told me he ain't really into it only is cause I am.. so basically I feel like he was faking the moaning and all that..

Idc that he don't like it.. like it is fine.. but what makes me start to over think is that obviously he faked enjoying it.. what else does he fake