Mattheo Riddle. 03

You entered the potions classroom and looked for a free seat but the rest of the students were already seated. Mattheo was leaning on a table so you approached him.
"Excuse me. Can I have this seat?" You asked politely, smiling. Without turning around, he joked;
Mattheo: "I'm sorry, I think it's school property."
This caused giggles from his friends. He then looked at you and his smile disappeared.
Mattheo: "Yes. Of course."
He muttered as he stood up from his seat