Umine the Island Inn

Kazuma Shiozaki, a 19-year-old high school graduate, has just arrived in Asagiri Island to work at Umine Inn, an all-female boarding house and cafe run by his aunt Aya. Asagiri is said to be home to long-lost pirate treasure. While there, he gets to know the inn's residents, all of whom have their own eccentricities and interests. As Kazuma learns to adjust to island life, he finds out that life here is more interesting than he initially thought.

Kazuma Shiozaki (潮崎 一馬, Shiozaki Kazuma)

The protagonist, he moved to Asagiri Island in order to look for work, having been unemployed since graduating from high school. He is skilled in martial arts, having been trained by the Tsuruga school. He is implied to have trained under Ami Tsuruga, a character from Seo's previous series The Café Terrace and Its Goddesses.

Yuna Asagiri (朝霧 夕凪, Asagiri Yuna)

A high school student and a resident of Umine Inn. She is cold towards Kazuma when they first meet, but she quickly changes after he saves her from an encounter. She is interested in finding treasure on the island told to her by her late grandfather, and wants Kazuma's help in finding it.

Rinko Ichinose (一之瀬 凛子, Ichinose Rinko)

A resident of Umine Inn, who currently works as a hostess.

Iori Sugiyama (杉山 伊織, Sugiyama Iori)

A 21-year-resident of Umine Inn, who moved to Asagiri Island to take over her late grandfather's sake business, turning it into a shōchū distillery. She previously worked at a factory in Tokyo.

Sakura Shindo (新堂 桜, Shindō Sakura)

A girl who moves into Umine Inn. She met Kazuma a year prior to the start of the story, after he rescued her while he was training in the mountains. She is secretly a kunoichi and arrived in the island after her family tasked her with killing Kazuma; however, as she has developed feelings for him, she is unable to push through.

Ren Nanakawa (七川 連, Nanakawa Ren)

Kazuma's childhood friend and rival, and a karate champion. She came to the island to defeat him, as he was the only person to ever beat her in a fight despite handicapping himself. Apart from karate, she also works as a fashion model and influencer, having about one million followers.

Aya Shiozaki (潮崎 彩, Shiozaki Aya)

Kazuma's aunt, who runs Umine Inn. She is his mother's younger sister.

Saki Shiozaki (潮崎 咲, Shiozaki Saki)

Kazuma's cousin and Aya's daughter.

Nagisa Asagiri (朝霧 渚, Asagiri Nagisa)

Yuna's older sister.

The series is written and illustrated by Kōji Seo, who began serializing it in Kodansha's Weekly Shōnen Magazine on January 14, 2026, two months after his previous series The Café Terrace and Its Goddesses ended.^[1][2] The first tankōbon volume was released on April 16, 2026.^[3][4] The series is also serialized simultaneously in English on Kodansha's K Manga service.^[5]