Actually, that's probably a joke about the common trope in Hentai: writing on a woman's body how many "turns" she had.
When you write 1,2...5 (like making 1,2... marks, then barring IIII to mark 5), the Kanji for Go(5) is:
五, very similar to Justice 正, all the more when drawn on a moving, chubby angel canvas 😁
Yay trivial knowledge! +1