I'm having an annoying time knowing what to tag this, due to the content. It's clear from certain scenes that You and Kanan have penises in this, but skipping the yuri tag altogether, as would be the case if it was a NSFW release, would be a mistake here. Maybe it could skip a futa or transgender tag altogether, a lot of people wouldn't notice (altho the one big joke scene is pretty clear), but I felt it was noteworthy enough to deserve notice. But it's honestly hard to say what to do here, it's such an uncommon scenario and not one I'm satisfied with the solutions that deal with it.
I'm open to ideas about how to deal with things like this, sfw doujins that skirt the line in content.
As for the doujin, awesome. Long form Pito is something the world needs a lot lot more of. And Yoshiko is the best wingman.
I feel like when in doubt, especially when its not meant to be like fetishistic, side with Trans and Yuri. It's not really used outside of a prop gag and perhaps tying it to one other comic (that side stepped this issue by picking all three) and honestly if you feel like you're stuck offending someone, you might as well offend pedantic people not actual trans people imo.
