Soikano: Gyutto Dakishimete - The Animation

Kouhei has lately been seeing dreams where he is falling, and it made him chronically sleep-deprived. So, he would take a walk every day around the school grounds for a comfortable place to take a nap during lunch break.

One day, he visited the rooftop greenhouse for the first time and took a nap there. When he woke up, there was a girl who he didn’t know sleeping next to him.

"Wah!? Why!?"
"Nn… This, is my, reserved spot…"

Yoake was a problem child at the school. Why is it that she never shows up in class even though she comes to the school? He begins to know her secret after napping together with her every day.

(Source: VNDB)