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Bl where there are two friends. The black haired dude had a sister that said anyone who isn't a virgin should die and the brother doesn’t get it till he has his first love. He realizes that he wants his first love to have their firsts with him only. Time skip where the first love lies saying he met someone because he thought the black haired dude found someone too. Black haired dude threatens to kill him until the first love confesses the truth. First love has dyed blonde hair but brown roots I think???