This is a section of a sketch -- a layer actually -- where Charlie and Beverly are having the last dance of the night at her graduation after party.
Beverly is going away to college and Charlie asked her to to stay faithful to him
The layers not shown is his car in the background of the empty parking lot, moon high overhead.
The is the AU where she leaves Charlie, and the seriousness and the sincerity of the question took her aback.
This is done in Painter 2020 with different Pencil brushes with the lines petted and erased.
I tried a few things: Beverly's permed hair, incorporating her KF markings into a younger face, and a more human feminine form.
I have earlier iterations and I may post one to scraps [ https://www.furaffinity.net/view/45063162 ] for comparison.
[Update 15 December, 2021] I cleaned up the share file, making a few changes that bothered me with Beverly's expression and cleaned up the drawing a little better.