Hobbies are often a great way of meeting new people, but how could Kakeru Diachi, who collects rare juice cans, have ever suspected that he'd meet a fascinating new girl when he attempted to DRINK her? Naming her Melon, because she's got great melon... soda, Kakeru quickly learns that she's an Akikan—a beautiful girl who's also a special can created to fight other Akikans in a strange experiment to determine what kind of container is better: steel or aluminum!