If your F/O has significant body hair-- imagine playing with it, gently or teasingly. Running your fingers over the hair on their arms, chest, stomach etc. Feeling the texture of it, whether thick or fine, under your fingers. Maybe even pinching or tugging at it, and making them blush.
Imagine your villainous F/O pushing you down, wrapping their fingers around your throat, and kissing you with a passion that overwhelms you completely.
stabbing as a metaphor for penetration is great but when are we going to talk about pressing down on where someone is wounded to disarm them or just to be cruel while fighting. does nobody else care about the perverse intimacy of knowing exactly where to touch to overpower someone. the grotesque vulnerability of it. especially if you're the one who wounded them in the first place.
imagine your f/o going "cute? me? i think you got the wrong guy" after you fawn to them about how cute they are, but its apparent that they're flustered by it !!
whether it shows itself through change in facial expressions or their body language, or showing itself in the way they start talking. especially when they're usually perceived differently. maybe even as somewhat offputting by the majority of people around them
they're relieved that you perceive them that way !! you thinking they're cute has something comforting about it
you finally confess your attraction to the hot priest and he's like "oh darling, I thought you'd never ask" and proceeds to bite your neck and turn you into another catholic priest