since she was a a kid she was so protective over osamu until he run away she and osamu ex-girlfriend and friend is heart broke so they swear to themselves to find the osamu dazai the heir of the dazai family -Atsumi- No matter that you teleport to the different universe i no we will find you osamu-nisama -blueberry- as your friend i promise i will find you Maou-sama -shiro- as a sister to your ex-girlfriend or ex-wife and also as your friend i promised that i will find you osamu.. -yashiro- even if i'm your ex-girlfriend i still care for you like the way you did care for me