When Enishi was an infant, his mother died and he was raised by his older sister, Tomoe. She raised him herself, becoming both sister and mother to him, and he grew to love. When Tomoe became engaged to Kiyosato Akira. Kiyosato is killed by Hitokiri Battōsai (Himura Kenshin). Tomoe left her brother behind to seek revenge, working with the Yaminobu to do so. When he was about ten, he discovered the location of Tomoe through the Yaminobu and appeared before her, revealing that he was the contact sent to Tomoe. While he believed that he was helping Tomoe's revenge, he did not know she had grown to love Kenshin.