"Rosario + Vampire" is a manga series set in a world where humans coexist with supernatural beings, though humans are largely unaware of their existence. The story centers on Tsukune Aono, an ordinary human who accidentally enrolls in Yokai Academy, a school for monsters. Initially unaware of the school's true nature, Tsukune quickly discovers that all the students and faculty are monsters, including vampires, witches, werewolves, and other mythical creatures. To survive, he must keep his human identity a secret, as humans are considered dangerous and are forbidden from attending the academy.

Tsukune befriends Moka Akashiya, a beautiful and powerful vampire who appears gentle and kind but transforms into a more assertive and formidable version of herself when her rosary, which suppresses her true power, is removed. Moka becomes fiercely protective of Tsukune, and their relationship forms the emotional core of the series. As the story progresses, Tsukune encounters other female classmates, each with their own supernatural abilities and personal struggles. These include Kurumu Kurono, a succubus seeking true love; Yukari Sendo, a young witch with a mischievous streak; and Mizore Shirayuki, a shy yet obsessive yuki-onna (snow woman). Together, they form a close-knit group that navigates the challenges of Yokai Academy.

The narrative explores themes of acceptance, identity, and the coexistence of humans and monsters. Tsukune's human nature becomes both a vulnerability and a strength, as he often finds himself at the center of conflicts involving rival students, dangerous monsters, and external threats to the academy. Over time, Tsukune undergoes significant development, gaining supernatural abilities through a series of events that blur the line between human and monster. His relationships with Moka and the others deepen, with romantic tensions and personal growth playing key roles in the story.

The series balances comedic and lighthearted moments with darker, action-packed sequences, as the characters face increasingly dangerous adversaries. The second half of the manga, "Rosario + Vampire II," shifts toward a more serious tone, delving deeper into the lore of the monster world and introducing higher stakes. The characters confront powerful enemies, uncover hidden truths about their origins, and grapple with the consequences of their choices. The story culminates in a climactic battle that tests their bonds and resolves long-standing conflicts, while leaving room for personal and relational growth.

Throughout the series, the dynamics between the main characters evolve, with Tsukune's humanity serving as a catalyst for change in a world dominated by monsters. The manga explores the complexities of love, loyalty, and self-discovery, set against the backdrop of a supernatural school filled with danger and intrigue.