After some back-tracking, I feel I can definitely say that he didn't draw it. But, I'm not sure how much of a hand he had in it, or lack thereof, as it's part of their collaboration on the parent pic. Sadly, the artist deleted it (apparently... unless he let Takatora upload it directly to his own), so it can't be sourced.
At any rate, I'm happy the artist could even be found (wish I had noticed the collab pic, first. Takatora linked the artist, would've saved me a lot of trouble, lol). Many a good pic gets lost in Danbooru and tracking their origin is painstaking, usually with no results.
