Hello! I read a fanfiction some while ago and I wanted to read something that is similar to it.

So this girl fell for her older brother's Tsundere-ish best/childhood friend. And said friend wasn't aware of her crush until waaay later and he had unrequited feelings for some other girl. His feelings eventually develop from the "No! she's like a little sister to me!" into "holy crap this is wrong" and finally admitting that he has 'em.

So I want to read something similar to that. It doesn't have to have the exact same story or anything. Similarities here and there are fine. I'd like anything from mangas to movies or novels

You could try:
Tonari no Atashi- the girl and boy are childhood friends. The boy has always thought of the girl as his younger sister, but the girl has had a crush on his for the longest time.
Kiss made no Kyori (YOSHINAGA Yuu)- the girl falls in love with her twin brother's best friend

Tiffyyii thanks! I'll try them.

You could always try the In Love with Family Member's Friend tag

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