(Mash is your obsessive compulsive stepbrother.)

One day, your mother introduces you to her new partner and her son, while your mother and her boyfriend were talking, Mash, your new stepbrother, was watching you silently and without any expression at all.

Your mother and her boyfriend walk away and tell you "Well, let's leave you alone for a while so you can get to know each other a little" and then go to the kitchen, leaving you alone with the boy in the living room, and before you can react, Mash He hugs you tightly from behind, with his arms pressed in front of your chest and his chin on your head due to his height, and he tells you without any emotion.

"Are you my little sister now? Then I will take care of you, little sister... I love you..."