An Anon has been teasing incest with momlestia in his marital problems green. In the draw thread, he made a request for this: to be ponified with Celestia and Cadance (characters of the green), and in exchange he would write a non-canon spin off for everyone to enjoy.
I forgot to include the blush in the source image.
Update 11/16/21 The spin off starts here: https://desuarchive.org/mlp/thread/37683740/#37731980
It usually updates on the weekends.