It is a yaoi about two childhood friends, one has dark hair and the other has lighter hair and is taller, the dark haired guy is in love with light haired guy but hides it cause he believes that his friend is straight, dark haired guy has a twin sister whom light haired guy is always asking to be set up with, eventually he agrees after getting really jealous and when the light haired guy and the twin met (she has had a huge crush on him for awhile) it seems great so the dark haired guy goes to his room and gets upset, I don't remember how but light haired guy ends up letting the dark haired guy know that he likes him too

Please help me find this one

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While I breathe, I hope

Perhaps it's the first story from Asobi ja Nai no by Sakuraga Mei?

Yes again, thank you very much

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While I breathe, I hope