Suzu, a solitary college student who shields himself from the world with a mask, suffers the loss of his beloved partner Kappa-chan. Aiji Sasamuro, a suave and charismatic figure, and his flashy entourage discover Kappa-chan and taunt Suzu by refusing to return it. However, upon its safe return, Kappa-chan bears significant damage, leaving Suzu devastated.
Aiji subsequently comes back into the picture, demanding affection and gratitude from Suzu, despite their mutual antagonism. Unexpectedly, Aiji and Suzu's relationship takes an unforeseeable turn when Aiji pecks Suzu through his mask after being labeled a "land mine." The tale chronicles the romantic connection between Suzu, a shy individual with communicational difficulties, and Aiji, a celebrated and charming man familiarized by their adoration for Kappa-chan, an enigmatic and charming being.
