I'll Take Shelter From the Rain With You.

High school first-year Teru Aoki is a loner who does not have a place at home nor in his class. Kokoro Amamori is a girl one year his senior. Two people who cannot seem to fit anywhere meet in front of the closed-off doors of the school rooftop. As they spend time together, they slowly start to understand each other. (Source: Kadokawa, translated)