I was wondering that as well. His design seems too distinct for him to be just a random extra for the school scenes, plus past chapters have shown that he seems to be part of the popular clique with Saeki and Akagi. However I kind of suspect that if he's going to become a sort of rival later on, he wouldn't be after Saeki, thus being Tokimiya's rival, he would instead go after Akagi, and be Mishima's rival. I hope neither is the case and he's just some guy, however I just have a sneaking suspicion that his purpose is less innocuous. Again, I hope my suspicions are wrong.
Seeing some remind the famous 177013, i did try read some and gotta say it very... overrated. Like it feel flat, more mess up stuff keep happen but i feel nothing about it. There are more tamed work, but trigger me better