Nanoha Mukoda was a Japanese prostitute who lived in Yokohama. The daughter of Tatsuro Mukoda and the twin sister of Saeko Mukoda, she worked a white-collar job before her father fell ill, upon which she approached her sister's employer Isao Nonomiya and persuaded him to give her a job at his Otohime Land soapland so she could raise funds for her father to be cared for at Sunlight Castle. After the retirement home's director Yamato Totsuka demanded millions more yen for an emergency surgery, Mukoda began seeing clients on the side in order to scrounge up the extra money, causing Nonomiya to hire Ichiban Kasuga, Yu Nanba, and Koichi Adachi to infiltrate Sunlight Castle and investigate Mukoda's predicament. The group ultimately exposed Sunlight Castle as a healthcare and pension fraud, leading to its closure. Mamoru Takabe informed Nanoha that her father had been "misdiagnosed" and did not need a surgery, and that he would be moved to another care home free of charge. Nanoha was able to leave the soapland behind to return to a more profitable line of work, although Nonomiya was murdered by the Yokohama Liumang that same day.