"After School Midnighters" is a surreal and comedic anime/manga series that blends elements of fantasy, mystery, and school life. The narrative centers around three middle school students—Hikari, Nozomi, and Miko—who discover a hidden world within their school after hours. While staying late one night, they encounter a talking skeleton named Skeletos, who reveals that the school transforms into a bizarre, otherworldly realm at midnight. This alternate dimension is filled with strange creatures, magical artifacts, and puzzles that defy logic.

The trio embarks on a series of nocturnal adventures, solving riddles and navigating the school's surreal landscape to uncover its secrets. Each episode or chapter introduces new challenges, often tied to the school's history or the personal lives of the characters. Hikari, the pragmatic and curious leader, often takes charge, while Nozomi, the timid but resourceful friend, provides emotional support. Miko, the eccentric and imaginative member, adds a layer of unpredictability to their escapades. Skeletos, though initially cryptic, becomes a guide and ally, offering cryptic hints and comic relief.

The story explores themes of friendship, curiosity, and the transition from childhood to adolescence, all while maintaining a lighthearted and whimsical tone. The school's midnight world serves as a metaphor for the unknown and the challenges of growing up, with each adventure reflecting the characters' personal growth. The series balances humor with moments of introspection, creating a unique blend of absurdity and heartfelt storytelling. Through their nocturnal explorations, the characters learn to confront their fears, embrace their individuality, and strengthen their bond as friends.