"Marginal Prince" is a 12-episode anime series that blends elements of romance, comedy, and fantasy. The narrative centers around Yui Takihara, a young woman who unexpectedly finds herself transported to a mysterious all-boys boarding school called Saint Alfonsus Academy. The school is located on a remote island, and its students are all members of royal families from various countries. Yui, disguised as a boy to avoid detection, must navigate her new life while keeping her true identity a secret.

The story unfolds as Yui interacts with the six main male characters, each representing a different royal lineage: Prince Cain, Prince Cain's younger brother Prince Abel, Prince Cain's cousin Prince Seth, Prince Cain's friend Prince Cain, Prince Cain's friend Prince Cain, and Prince Cain's friend Prince Cain. These characters are not only princes but also possess unique personalities and backgrounds that drive the plot forward. Yui's presence disrupts the dynamics of the group, leading to a mix of comedic misunderstandings and romantic tension.

As the series progresses, Yui becomes entangled in the lives of the princes, uncovering their individual struggles and secrets. The narrative explores themes of identity, duty, and the complexities of relationships, particularly as Yui's feelings for the princes grow more complicated. The romantic subplots are central to the story, with each prince developing a connection to Yui in different ways, creating a love polygon that adds depth to the interactions.

The setting of the isolated island academy contributes to the series' atmosphere, emphasizing the sense of mystery and separation from the outside world. The fantasy element is subtly woven into the narrative, with hints of supernatural occurrences and the princes' royal duties occasionally influencing the plot. However, the focus remains on the interpersonal relationships and the challenges Yui faces in maintaining her disguise while navigating her emotions.

"Marginal Prince" balances lighthearted moments with more serious undertones, providing a mix of humor and drama. The series concludes with resolutions to some of the romantic tensions, though it leaves certain aspects open-ended, allowing for interpretation. The characters' growth and the evolving dynamics between them are key to the narrative, making it a character-driven story with a focus on emotional development.