They don't *outsource* the graphics, he's a team member and doesn't draw for any other lewd games.
Well, I can't tell with full confidence for nowadays, but somewhat about a year ago there was a discussion on a Russian site with similar to F95 theme (adult games, etc) in which mentioned above Tobie (I'd misspelled his nickname) took part. And the answer to logical question "Why the fuck there are so large intervals between updates of your game?" among other reasons (such as script re-writing, which is a warning sign of it's own (if you "played" this game, especially it's previous builds before whole adventure re-work, you should know that Tobie LOVES to write A LOT)) was mentioned that they have to wait for the artist(s?) to draw content for them and every other thing (especially script, dialogues, etc) was ready for future updates.
So, in sum, the only thing that was keeping them from updating more frequently was graphics. So what does responsible head developer does when this sort of situation happens? Hire additional artist, simple. And they always had money for it, even when there was no content whatsoever for about a year (in between Witch Trainer and that pathetic thing that was 0.0.1) they were sitting on more than 2.5k+ on Patreon, so they had the money for it.
Their "business" model is simple - sit on as much money as they can while releasing as little content as possible. Are they within their rights to do so? Absolutely, just as I (and people with similar to mine mindset) am within my rights to despise them for it.
P.S. To people, who are wondering about actual content - you will have to be very patient about this, because Tobie thinks that he is a wonderful writer and his dialogues, script and story are literally masterpiece that he must share with others to appreciate and they can not under any circumstances be altered in any form. And no, he is not redeemable, everyone (including me) tried and failed to make him realize that he is nothing but a graphomaniac with overblown ego.