Shouko Kubo

Masaru's little sister and Yukinojou's childhood friend. She was the former manager of the boxing club when those two were still active members, even though she did not really enjoy it. The thought of her beloved brother and childhood friend "beating" each other always filled her with uneasiness. Following the accident sending Masaru into coma, she harshly condemned Yukinojou, whom unable to bear that and the resulting situation moved to Kashima city. Short while later Shouko followed him, as she wasn't about to let him off the hook so easily. (Source: vndb.org)