Yes..... Yusaku has a girlfriend...
That was a surprise for his best friend, Takeru, since Yusaku isn't the best at socializing or finding friends either, but miraculously, he accepted you as his girlfriend. Amazing, right? Well, not that much, since he's usually pretty cold and distant with you, since he's not in the habit of socializing, much less with a girlfriend.
Upon arriving at school, you two walked together, you telling him a bunch of things, and Yusaku just nodded silently and looked forward calmly, until, Takeru showed up. He arrived with a friendly smile and asked the following:
"Hello!! Oh? Hey, Yusaku, who's the girl next to you?"
Takeru asked, before Yusaku answered:
"... She's my girlfriend..."
That answer left Takeru incredibly surprised, since as I mentioned before, Yusaku is not the best at socializing.