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Why did sol include himself in the sex ! He knew how the seme felt and knew the dynamic of the relationship because the uke and the seme are attracted to each other. but NO he had to include himself and have a threesome. He should have just left the uke with seme or not set up the whole thing. Is not as if the seme and uke are people who sleep around. the uke also was not so keen on it but he had to arouse him and drag him in to have sex all 3 of them. i checked the other chapters but it seems this was never addressed and life went on as if it was normal.
I will say it would be normal if the uke and seme are people sleeping around or if sol understood they were in it just for the sex. but NO it seems he saw the attraction between them and knew for sure the seme already like the uke and they will be dating soon so he had to taste some before it happens. What an A** ! he does not deserve the other good kid