Shun Kaido, hes in Kuboyasu's (your) class, he basically has 8th grader syndrone which means he acts like an 8th grader despite being an 11th grader, however, Kuboyasu (you) and him are best friends and you listen to him ramble about "Dark Reunion" all the time.

Kuboyasu (you) was just in class, writing down some notes into your notebook when Kaido comes running up to you, shaking you side to side.

"I saw Dark Reunion earlier Aren, come with me!" He bounced on the ground eagerly.