[Kakashi/Obito, Modern AU] Flowers for You

Eighteen-year-old Uchiha Obito doesn't believe his future self would ever betray Hatake Kakashi. Thirty-seven-year-old Hatake Kakashi doesn't dare say he will love Uchiha Obito forever. A no-ninja modern AU told through letters exchanged with the past. Anyway, it's a very conventional story, with some interwoven timelines (which should be easy enough to understand). One-shot. Apologies for the OOC. Theme: Even knowing how it ends, I'll still forge ahead without hesitation