Description

Iwaizumi Hajime: Iwaizumi hits Oikawa for mocking Karasuno
Apparently, Iwaizumi is a somewhat stubborn person, but a clearly reliable teammate. He is often the point person for Oikawa to give the team a morale boost if necessary.
He acts supportively with everyone, including Tobio Kageyama, and is also responsible for reprimanding Oikawa for his childish antics. He often resorts to violence with Oikawa, but this doesn't change the fact that he cares deeply for him, as shown when he makes an effort to stop Oikawa because he works too hard or loses confidence.
He has a firm attitude, even leading some members of the Aoba Jousai team to look forward, resulting in the team having great respect for him, even more than their captain.
Oikawa Tooru: Despite his flirtatious nature (which makes him very popular among female students, both Tanaka and Nishinoya are envious) and childish attitude (as noted by his nephew and Iwaizumi), Oikawa is an excellent player, well-rounded, and very serious when it comes to volleyball. He knows he has an "unpleasant personality" among some opponents and his own teammates, caused by his petulant attitude. Oikawa also frequently makes cheerful comments but follows them with a serious or intimidating tone. Despite his flirtatious and indifferent exterior, Oikawa is extremely intelligent and astute, to the point where his own teammates indicate they don't want to be friends with him, because he notices everyone's weaknesses (Oikawa responds indignantly by asking why he would do that to his own teammates).