Responses
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I don’t wanna confuse no one but these are little things I can remember
- green jacket?( that’s how he ends up kissing the guy he doesn’t like because he had on the jacket that belonged to the guy he was trying to confess too)
- silver hair? and the other had blonde( I’m sure about the blonde)
- maybe alley way Throws up after kiss
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sorry my answer isnt bl but your description sounds so much like this one http://www.mangago.zone/read-manga/lovely_again_today/
From what I could remember
It was a company dinner, and the main guy mustered up the courage to confess I think to his boss but he ends up kissing a guy( I believe they hate each other or something like that and that’s it