An artificial island in Tokyo Bay—Kyokutou Houreigai Tokubetsu Chiku (Far East Special District), commonly known as the 24-ku (24th Ward). Childhood friends Ran, Kouki, and Shuuta, who were born and raised there, have different family backgrounds, hobbies, and personalities, but always hung out together. However, their relationship changes drastically in the wake of a certain incident. At the first anniversary memori...