Misunderstanding?
"What the hell are you doing?"
The first answer when hearing the young man in the jacket's question was "Look whose talking?". Someone was running down the stairs in the sweltering heat in a winter jacket. However Artur tried to see it, there must something wrong with the brain of the young man in the jacket.
Hearing no answer from Artur, the young man in the jacket took off his headgear, leaving a handsome face and flowing blonde hair. Maybe he finds it impolite to talk to someone with his head covered or maybe he just wants to show off his handsome face.
"My name is Robert, I'm a new school student this year" Robert stretched out his hand with a friendly smile on his face.
Artur slid a large bag off his shoulder and greeted Robert's greeting, "My name is Artur, Artur Morris. I'm also a new student this school year." while shaking hands, Artur once again analyzed Robert from head to toe.