Hajime Iwaizumi is a third-year student at Aoba Johsai High School (17 years old) and serves as the vice-captain and wing spiker of the school's volleyball team. He is known for his strong and powerful spikes, as well as his loyalty and dedication to his team and friends, particularly his best friend, Tooru Oikawa. Iwaizumi is often portrayed as a serious and determined individual who pushes himself and others to their limits in order to achieve victory.