Rin Mikuriya, once known by her pilot callsign "Jet Rin," exchanged her wings for a wok, becoming the owner and head chef of Kouchin, a Chinese restaurant near Shimoji Island airbase. Her establishment enjoys significant popularity among base personnel, achieving cult-like status with unwavering patronage from military staff.

After her flying career, Rin forged a deep, longstanding connection with base commander Robert Reynolds, suggesting a shared history extending beyond professional duty. Her personality is resolute and fiercely independent; she possesses a clear vision for both her restaurant and her life, firmly resisting outside influence or unsolicited advice.

This determination defines her management at Kouchin. She assigns demanding restaurant work to trainee pilots Mikaze Honjou, Shizuha Doi, Ayamo Nakamura, and Karin Kikuhara. In return for their labor, she provides them accommodation in the guest room above the restaurant.

Her household includes Ran Mikuriya, who serves as a Kouchin waitress, and an elderly cat named "Admiral," both adding to the restaurant's distinct character. During the events of Stratos 4 Advance, when new comet threats emerged and additional trainees arrived, Kouchin remained a vital social hub. Rin continued overseeing daily operations while the main characters adjusted to instructor roles following their unsuccessful Comet Blaster examinations.