Sister Princess is a tV series anime that premiered in spring 2001, produced by ZEXCS.

About the production: the story comes from a light novel, there are 26 episodes of about 23 minutes and its current status is "finished".

Its main genres are comedy, drama, romance and slice of life, with themes such as Female Harem, Incest, Ensemble Cast and Family Life.

On AniList, Sister Princess has an average score of 60%, an average score, and appears on 5,969 users' lists.

Wataru Minakami is a top student who failed his high school entrance exam because of a computer glitch. He later discovered that he was accepted to Stargazer Hill Academy, which is located at a mysterious place called Promised Island. At the request of his father, Wataru is whisked away to the island, and before he can settle in, a dozen of cute and charming girls start to flock him and claim to be his younger sisters. As Wataru gets closer to his newfound siblings, a deeper mystery as to why they were sent to the island comes to play. (Source: Anime News Network)

Official synopsis from AniList.