Final Fantasy XII, Vaan/Penelo, muscle-memory
The way his hands move over her, late at night when there is no one to see, when the airship is on silent and resting in some spot in the desert, is so familiar to her and so comforting to him that even when he is blind and wounded and the blood leaking from great gashes in his back that only running his hand over that exact spot will calm him.
And only that exact spot, between her shoulder and her neck, will make her jerk from bandaging his wounds or healing them with her magic. Jerk, and knock over what she had been holding.
Later even in the darkness, even when he is half-dazed, his hands can still tread their way around her body, under her breasts and cupping her nipples, his hair down-soft against her body.
Later even when he cannot move she rolls over on top of him and he moans into her mouth and takes his pleasure after he gives her hers, and the only sound the both of them try to make are little whimpers.
And even in caves, pressed up in little cracks when only the faintest rays of light cascade through, his hands can still find the exact spot that makes her legs part, the exact run of skin between her ass and her delta that makes her putty in his hands, willing to be guided and shaped.
Of course, it isn't all his memory. It is hers, too, coming home after a night dancing in Rabanastre's streets, exhausted and mind half-blocked from the lecherous grins of the men there. Sometimes it is safer and more comfortable for her to hold his dick and move it in slow movements and feel the veins and the skin's texture and concentrate only on the way his voice is coming in short gasps and bring all the memories of the gropes and leers to the back of her mind where they can be lost forever.
And sometimes their muscle-memory and their subconscious comes out at the most awkward of times, when Vaan is just patting Penelo on the back and subconsciously finds the spot that makes her hips buck upwards, much to the consternation of Penelo and the delight of the man she is bargaining with.
(He wasn't so delighted after Penelo conked him one over the head with her staff.)
And even though their sex is almost homely, an everyday constant like brushing their teeth or taking a shower (only rare breaks when they don't, and they feel incomplete when they don't - or at least, Penelo does about the showers, Vaan's more about the sex) they try to make it different when both of them aren't mind-dazed and actually want to do something special.
The way they rock in each other - or, more precisely, the exact sequence Penelo clenches her muscles when Vaan takes her in any way he can - is all memory, too, albeit some of her best memories.