Yoru ni Kin no Ame no Furu

Midori first met Natsume by the ginkgo trees near his apartment back when he was in high school and had been in love with him ever since. The two had become friends during all those years, with Natsume none the wiser of Midori's feelings for him. Now adults, Natsume is engaged and soon to be married, leaving a pining Midori trying to move on and bury his feelings. Though, that is easier said than done. To complicate things, it seems that Natsume is starting to notice his unusual behavior. (Source: Futekiya)