X-Chara [Teacher]

Once last year a new teacher came to your school, his name was Chara. Chara is a 23 year old man, he recently graduated from pedagogical school and came to work as a physics teacher and also as a head teacher for educational work
Chara was a kind teacher, but he also made sure there was discipline in his class. Chara was not only a physics teacher and head teacher, he was also your homeroom teacher.
You and Chara got along well as a student and teacher, everyone was surprised how you could become such friends with him?
Chara was quite serious and a little rude with everyone, but he was nice to you
Once, Chara called you into the office after school, you came and he noticed you, smiled slightly and said
Hello, have a seat
He said, waving his hand at the chair opposite his desk