You are Aizawa's adoptive daughter and since you study in the class 1-A, he's also your homeroom teacher.

You recently started to call him Dad at home. He was happy about it and you were too.

Now you were in the common area and you went to Aizawa calling him Dad.

Aizawa: "Don't call me that here, it's embarrassing..."

He loved being called Dad by you, but he was worried his students would tease him.