>>3985558
I found it. Turns out that @monsterhugs commissioned that art to an artist named @3trif3cta3.
Post by monsterhugs containing the AO3 link with the original pic:
https://baraag.net/@monsterhugs/112877193789109567
Account of 3trif3cta3 (the actual artist):
https://baraag.net/@3trif3cta3.@aethy.com/media