well no. they're not. bc kusaka's dad had a relationship with mizutani's mom and then mizutani's mom died so no. they could've been half brothers but they're not.
I think mizutani's child was from another man since he work as a prostitute, maybe he got pregnant when he ran away from the seme's dad, since they're just college students at that time
......................................................the seme is virgin.
Yeah he is. The uke's got experience so he was the one to lead the first time
Please put the link of the raws