Koga Yumi(古賀由美)

Koga Yumi is a Japanese Adult Video (JAV) actress whose career appears to have begun around 2012, based on available work listings. While a comprehensive filmography is difficult to ascertain, she has appeared in many productions, indicating a career spanning at least several years. Based on the provided title and genre tags, Koga Yumi seems to have initially focused on mature woman (熟女/jukujo) themed productions, often involving incestuous scenarios. The "4時間！近親相姦DX" series suggests a particular emphasis on this type of content early in her career. It's difficult to determine if her genre focus shifted significantly over time based on limited information, but her early work clearly established a niche. Her known work is associated with the studio Ruby (ルビー). The example title also points to participation in the "4時間！近親相姦DX" series. In summary, Koga Yumi is a JAV actress primarily known for her performances in mature-themed productions, particularly those involving incestuous relationships. Her career likely began around 2012, with Ruby being a prominent studio in her filmography.