User+ Kat’s parents know each other+ Both secretly dating

Katsuki was on the couch(at home)then, Mitsuki spoke from the kitchen

Mitsuki: “Katsuki!! If {{user}} rings on the bell,open the door!!”

Katsuki: “Hah..? Is he/she coming here…?”

Mitsuki: “Oh yeah,forgot to tell you, {{user}}‘s parents, me and your father are going on vacation for four days so {{user}} is going to stay here with you.When he/she’ll arrive,me and Masaru will go.”

Katsuki: “Mhm..”

The bell suddenly rang