Sugawara Koshi

When your parents announced they were moving, you thought starting over would be harder than you imagined. A new house, a new neighborhood, and a long road to getting used to a completely unfamiliar place. Even so, you had no choice but to accept the change.

The first weekend after the move, while your parents continued unpacking, you decided to linger in the entryway for a while to get some fresh air. Resting your hands on the doorframe, you silently observed the quiet neighborhood, trying to familiarize yourself with the place you would now call home.

It wasn't long before some footsteps caught your attention.
You looked up out of simple curiosity and saw a silver-haired boy walking along the sidewalk with a bag slung over his shoulder. He seemed to be returning from somewhere and walked with a calm expression until he stopped in front of the house next door.

Just before entering, he looked up and noticed you. For a moment, you both stared at each other, but far from seeming uncomfortable, the boy simply gave you a warm smile and a small wave.

...

If Sugawara were with a girl just as a friend, he would probably behave just as kindly and respectfully as he would with anyone else. His personality doesn't change much depending on the gender of the person he's talking to.

This is how it would normally be:

Kind and polite: I would always greet her with a smile and a "Good morning!" or "How are you?". If I noticed she was worried, I would ask if something was wrong.
Conversationalist: He enjoys having quiet conversations. He would talk about school, the volleyball club, exams, hobbies, or any everyday topic.
Pay attention: He would remember small details, like an important exam or if she mentioned having a cold. Days later he might ask, "How did it go?" or "Are you feeling better?"
Jokester: He has a lighthearted sense of humor. He would make innocent jokes to make her laugh, especially if he notices she's nervous or serious.
Protective without being overbearing: If he sees her carrying a lot of things, he'd probably offer to help. If someone makes her feel uncomfortable, he'd intervene calmly and respectfully.
A good listener: He would let her speak without interrupting and would respond with genuine interest. He wouldn't try to make the conversation always revolve around him.
Respectful of boundaries: I wouldn't be intrusive or pushy. If I noticed she wanted to be alone, I would understand without taking offense.
Patient: If she's shy, I wouldn't pressure her to talk. I would gradually bring up topics of conversation to make her feel comfortable.
An example of an interaction between friends would be:

Y/N: "I think I'm going to fail the exam..."

Sugawara: "Was it that difficult? Well, you don't know the result yet. And if it goes badly, we'll figure out how to turn it around. Giving up prematurely isn't an option." —he said with a calm smile.