Fem Beast Atsushi gets hungrier and more volatile on her periods and Fem Beast Akutagawa gets more aggressive (not really, she’s just in pain) during her periods. Worst time alive for the to sync for everybody else but they enjoy it lowkey. Fem Beast Atsushi is soft and warm and the mixture of her soft scent mixed with a tang of blood is familiar and comforting to aku. Aku’s the perfect weighted blanket for Atsushi when the cramps are on coming and she needs something to focus on. I think most of their periods involve laying in bed cuddling, with occasionally munchies (on better days, aku uses he ability to catch some evil doers for her girlfriend to eat). I think they binge watch golden girls