UGH. I know I'm not saying anything new here, and am just adding my voice to the chorus, but this seriously sucks. I wanted the author to write an arc that didn't revolve around Kase or Yamada being jealous for no reason (and jealousy still factors in with Kase's unreasonable roommate) but this is ridiculous. The entire setup is stupid, the stakes are nonexistent, it will mean nothing other than a few angsty panels and Yamada yet again questioning their relationship.
Which at this point, she really should. We've never been given a reason for Kase refusing to call Yamada her girlfriend (homophobia doesn't seem to be an issue) yet she acts super territorial with her. It's sad because this started as a cute pairing, but at this point their love story might as well be a guide on how not to have a relationship.