In RPs literally everything. In hentai, tons of stuff. In real life?
boys who wear girly clothes
boys with cat-ears/tails
being called "daddy"
Leashes and restraints
Spit (really love messy sloppy kisses and blowjobs)
Cum (Even though I'm a top, I would have no qualms drinking your cum all day long. I also like being covered in it, and for my uke to be covered in it. Cum massage <3)
Sweat (especially sweaty balls)
I like armpits a lot for some reason. I just like to bury my face in them.
And I can't stress it enough, boys who wear girly clothes. I want my uke to be like a boy from HardBlush or Poju, dang it. Wear arm and leg warmers, chokers, panties, and tiny tight shirts and shorts, and I will die by the sword for you.
I'm sure there's more, but yeah.