Choosing a high‑school club to join can feel overwhelming. After all, the day offers only limited hours and, on top of that, a clash of interests between engineered beings and half‑canine girls. That is the dilemma Haruki Komaba faces.
Airi Kuze excels in mechanical sciences and harbors a crush on Haruki. Ayana Hizuki, a half‑dog, half‑human chemist, also admires him. Unfortunately for Haruki, he inadvertently pledged to join both clubs, landing him amid a heated struggle over his membership—and if Airi has any say, his future marriage.
The school"s annual club fair is drawing near, adding urgency to the decision. Friends urge him to weigh responsibilities, yet his emotions pull him toward both groups.
Things grow even more tangled when Ayana"s lewd older sister Touko steps in to support her sibling, injecting her own provocative chemistry into the fray. Haruki will have a hard time choosing a club, provided the girls don"t first tear each other apart. If they don't split, he'll still be stuck.