(About affectional and sexual relations between men, with some discussion of sex in street language, so this posting is not suitable for kids or gay men.)
A sale ad from Lucas Entertainment (the gay porn studio) yesterday (2/18) shows an affectionate couple, both smiling, but in different ways:
(#1) (The photo has been cropped, for WordPress modesty; but not only is the man on the left significantly taller than this partner, his dick is significantly longer and (especially) fatter than his partner’s)
On the left, an assured half-smile, directed at the viewers; on the right, an adoring (and adorable) half-smile. The men are presented as a b/t couple (in the terms I use for roles in gay male relationships): the t man is in charge, indicated by (among other things, his firm proprietary hand on the b man’s neck, while the b man is nestled against his partner, resting on his chest.
The b man often takes the bottom (receptive) role in anal sex, the t man the top (insertive) role — hence, the labels b and t — and that’s very much the case in the porn episode this still is taken from, but things are much more complicated than that.