This artwork is by Ghostbun, and is the first ever fan art for the game (so exciting)!
Ghostbun describes the premise for this piece as imagining what would happen in a ‘bad end’ where the player was too busy laying eggs to leave and had no choice but to submit to being Nixie’s lover forever.
(Edit: Okayman is now Ghostbun, check out the updated link and follow their new account)