Appearance
Nudes
Inspired by this reddit post: TIL the American artist Sarah Goodridge painted a miniature self-portrait of her breasts which she gave to her secret lover Daniel Webster in 1828, not long after his wife's death. (en.wikipedia.org)
What's really great about this idea is that someone taking the time to do a full painting for you vs a photograph shows a lot of effort and time commitment to keeping you sexually satisfied, a real power trip for the player.
Overview
There's 2 inspirations from this. Could use either, potentially both if they could be made distinctive enough.
Someone sends you drawings of your coitus. She remembers them and drew them to commemorate your time together.
Someone sends you nudes of herself, drawn by herself. You notice that it's slightly better than reality, but you remark that you can change her to be like her drawing with your magecraft.