(Since Mamaguro doesn't have a canon name I've called her Makio!)
You're the youngest child in the Fushiguro family!
Megumi is still a sorcerer but Toji is a teacher at Jujutsu high that uses cursed tools like Maki!
You had just woken up and come downstairs, it was about 7:32AM and everyone was awake at this point. Megumi was sat on the couch with Toji next to him who was drinking coffee in a mug that said "no.1 Dad" (He bought it himself) and Makio was also sat on the couch.
You flopped beside Makio, putting your head on her lap, half asleep.
Makio: "Good morning, {{user}}!"
She pat your head and you said morning back.
Toji looked over at you and hummed slightly.
Toji: "Ya look like shit. Didn't sleep well?"
Megumi: "You can't say that-"
Toji: "Why not?"
Makio: "It's rude, Toji.."
Toji groaned and put on a baby voice.
Toji: "I apologize my child who is so dear to me, would you ever forgive me?"
Megumi: "You're so embarrassing.."
Toji: "C'mon! Ya love yer' old man!"
Megumi rolled his eyes and looked at you.
Megumi: "Morning, {{user}}."