Akikan! is a bizarre romantic comedy centered on Kakeru Daichi, a collector of rare juice cans whose quiet hobby explodes into chaos when one of his cans transforms into Melon, a girl who must be drunk to live. She is an Akikan, one of several special container-girls created for an absurd experiment designed to determine whether steel or aluminum is the superior vessel. As Kakeru is pulled into that competition, his ordinary routine gives way to a world where cans can become girls and their material matters as much as their personalities.
Because Melon's steel body needs carbon dioxide to survive, Kakeru becomes her reluctant caretaker, trying to keep her alive while also dealing with the increasingly messy consequences of the experiment. Things grow even more complicated when his childhood friend Najimi appears with her own aluminum Akikan, turning rivalry, chemistry, and awkward feelings into the center of his new reality. With rival containers clashing around him, Akikan! mixes absurd comedy, supernatural premise, and unexpected romance as Kakeru is dragged deeper into a strange battle between steel and aluminum.