Ep. 1: Mikoto Urabe and Akira Tsubaki bond through her unusual saliva exchange ritual

1

Transfer student Mikoto Urabe is considered eccentric due to her strange behavior. Akira Tsubaki discovers her saliva has medicinal properties when it cures his fever, which Urabe explains is withdrawal from her fluids. They begin meeting daily for this exchange. Tsubaki develops romantic feelings and agrees to Urabe's condition for a relationship: he must destroy a photo of his middle school crush to prove his devotion. Urabe reveals her earlier laughter stemmed from a voice predicting Tsubaki would be her first sexual partner. Consequently, she accepts his confession and becomes his girlfriend, establishing their unique connection based on this specific biological dependency.