I don't remember much but the story involves a boy in love with his friend who has a girlfriend. His friend saves up money to take out his girlfriend on dates but they later on broke up. But his friend suggested to use his savings to still try the planned dates with the boy. The boy agrees and they spent their summer together. The friend invited the boy again to a festival, but later informed the boy that her ex girlfriend invited her to spent time with her looking around the festival. Heartbroken, the boy lied to his friend being sick and cannot go to the festival.

Sorry if my storytelling is trash but please help me. Im dying to read it again 😭😭

I read this not long ago! I'm pretty sure is Natsu no Teppen ni Saku
https://www.mangaupdates.com/series/hlq8d6r/natsu-no-teppen-ni-saku

No thoughts, only yaoi (and Uki Violeta)