For me, I love petite muscle bottoms under 5’2 tall. Something about a bubble butt taking my thick cock and feeling their ass lips grip my cock as I pull out is a feeling like no other. In my mind I just think about all stretching that is going inside of him, his organs being pushed to accommodate my cock, his breathing getting harder the deeper I go. I like that sense of power that this guy can’t undo what I’m about to do to him and I can overpower (consensually) him at my will. His little muscle body is nice and fit but even so he can’t overpower me.
I also put myself in a mentality where the guy is just there for my pleasure. His only purpose is for my pleasure and I love the sense of dominance that comes from that, especially if the bottom is into it but pushes back a little, albeit to little success.
For the record, there are a lot of petite muscle bottoms in my city. Many of them Latinos and Filipinos.