Kimi wa Kowareta Ouji-kun

The story revolves around 3 childhood friends. The main girl, the lighter haired boy (Natsuki), and the black haired boy (Aoi). Aoi was adopted into Natsuki's family. Main girl's home is really cold; her mom isn't home often and her dad is absent. She's into photography, is a little hot-blooded, and not popular with guys. She considers her childhood friends her place where she belongs. Natsuki is a playboy, and is into basketball. He also finds his friends to be the most comfortable place to be. Aoi is really quiet, said to have a bad personality among others because he only responds to his two friends. He's really smart.

 

The MC likes Natsuki, but Natsuki keeps joking that she's not even a female to him. Natsuki keeps unintentially jabbing her by saying that they're just childhood friends. MC resigns to that. She wants to give up on him, but she hasn't been able to for 10 years.

 

Natsuki gets a girlfriend and MC cries over it in secret. Aoi knowing this, tries to comfort MC. As MC is leaving, she falls and accidentally kisses Aoi. Aoi then decides to blackmail her: He won't tell Natsuki about MC's feelings if MC will date him [in secret]. Natsuki has no choice to accept.

 

NOTE: It's been somewhat implied/teased that Natsuki might have feelings for MC.