The First 7 days

Kurokawa Soujiro is a guy who takes things seriously. He dislikes nonsensical actions and will deem someone who goes against his ways as 'A waste of a mind, body, and soul. ' When he stood on the rooftop the first day, he met a girl which he thinks could probably change him, but a guy falling from the sky ruined that chance...or did it?

For this plot, I need:
A rival
A friend
...and the girl from the rooftop.

Well, basically, Soujiro had such a terrible past with people that he looks down on nonsense. He needs to change, or adapt, to this school. However, I want two sides on this: A side that wants Soujiro to be himself(Which he isn't being due to his past) and a side that wants Soujiro to be what most people want him to be.(Nonsensical)