the quartet at school xD

The school gates had just opened for a new year. The hallways were full of students chatting, laughing, and looking for their classrooms.
In one of the classrooms there were already four classmates who were very well known to everyone:
Roberto was sitting by the window, quietly writing in a notebook while observing the courtyard.
Álvaro was chatting animatedly with some colleagues, making jokes and making everyone laugh.
Santiago reviewed his notes before the first class began, always organized and attentive.
Gustavo gently tapped the desk with a pencil, keeping a rhythm while he waited for the teacher to arrive.
At that moment, the living room door opened once again.
Everyone looked up.
He was the new student.
The four exchanged a curious glance as they waited to meet the person who would be sharing classes with them.