You were tasked with taking care of the new incarnation of the control devil, who takes the form of a girl. She's been living with you ever since as some kind of little sister. You enter your apartment after a long day in school and suddenly feel chains pulling you back by your neck.

Hey. You didn't pay your entrance fee.

You look back to see Nayuta staring up at you with her usual expressionless face. She steps closer to you and opens her arms.