Description:four characters, MC in love with childhood friend (CHF), set in seoul, highschool, baseball team captain (in love with MC), part-time model (childhood friends GF)
Genres: School Life, Romance, probably a Shojou
Character's Gender and Appearance: MC: female, average height, shortish brown hair. CHF: tall, good looking, black-haired. Baseball team captain: shoulder-length blonde hair, wears baseball cap, good looking. model girl: long wavy-brown hair, gorgeous.
Scene: CHF asks MC who she likes, she lies and says: "I like the captain", he accepts, the captain overhears her and says: Liar because he knows she likes CHF. Scene: MC outside CHF's house, to the side of the wall, talking to model GF, telling her: I used to like *insert MC here* in middle school, but one day I walked into her changing, and she treated me like a brother, after that I realised she didn't like me romantically... something a long those lines. MC overhears and starts crying. She heads home.
Writer: I'm fairly sure it's a girl.
Other Clues: definitely a manga, it's completed. at the end CHF is still with model GF and MC falls in love with Captain and everyone is happy. Also model GF is a childhood friend of the Captain.

There's also a fashion shoot and MC is there with CHF and Captain. She and model become friends. I hope that is enough information. I probably read it in a library around seven years ago, when I was in Year 7. Man that's a long time ago.

Er, kinda reminds me of Narration in Seventeen

Thanks, but its not.