Blood on the Tracks 12 (manga)
Up on the hill, Seiichi's encounter with Shigeru merges with his own experience of being cast away by his mother, Seiko—and in that moment, he kills Shigeru in order to kill himself, a sacrificial rite to permanently sever his connection with his mother. Taken into custody, Seiichi feels only relief... But Seiko isn't gone from his life yet!!