OVA
Description
Midori Chitose transfers into the isolated all-boys boarding school Kanenone Gakuen during its co-ed trial period. She immediately forms an intense attachment to Yuusuke Takazaki, claiming they shared a past life as forbidden lovers who vowed to reunite in another existence; she retains vivid memories of this past connection, while Yuusuke initially recalls nothing. Her background is defined by this reincarnation narrative involving historical societal prohibitions against their union.

Physically, Midori has short brown hair, green tareme-shaped eyes, and stands 158 cm tall with a D-cup bust size. Her given name "Midori" translates to "green," referencing the series title.

Personality-wise, she exhibits an outgoing, cheerful, and carefree demeanor, often appearing oblivious to the social consequences of her actions—such as climbing onto a bedridden Yuusuke in lingerie or persistently clinging to his arm after class. Despite this seemingly naive presentation, she demonstrates academic intelligence and perceptiveness, understanding more than she outwardly reveals. Her devotion to Yuusuke drives her to comply with even inappropriate requests, like completing a perverted questionnaire from the Baka Trio hoping to please him.

Her relationship with Yuusuke forms her core character arc. She actively pursues him based on her past-life memories, creating a love triangle with Futaba Kutsuki, who develops feelings for Yuusuke after being rescued by him. Midori eventually prioritizes Yuusuke's happiness over her own desires, encouraging his relationship with Futaba. This culminates in her using her life force to save Yuusuke from a critical condition. Afterwards, the anime-exclusive character Reika Morimura returns Midori to the 31st century to preserve her life, erasing all memories of her existence except for Yuusuke's.

Across media adaptations, her role differs. The original visual novel establishes her as a main heroine without the past-life narrative, focusing on her efforts to foster harmony between the boys and girls while finding the Baka Trio's antics amusing. The anime adaptation introduces the reincarnation storyline and Reika's role, resulting in a bittersweet ending absent from the source material. The non-canon OVA "Erolutions" and game sequels like "Green Green 3" shift focus away from her central romance, with Futaba becoming the protagonist's partner in some continuations.