We Were There Vol 3

From the VIZ Media edition

Nanami Takahashi falls for Motoharu Yano, the most popular, carefree boy in class. For Nanami, it's first love, but Yano is still grieving the death of his girlfriend who died the year before. Every day, all day, I think about him. I wonder if there's a limit to love? I'm no longer able to imagine a world without him.

Source: Anime News Network Encyclopedia