SSIS-310 Jun Kouka, who was made to accompany my younger sister's intense fellatio training

``Is gender incompatibility the number one cause of couples breaking up?'' Jun, who just got a boyfriend, is worried about her technique... She practices with me (her brother) who lives with her! - ? - ``I don't want my boyfriend to hate me, so let me practice with you.'' From those words, the naughty relationship between the brother and sister begins! - My younger sister tries out various blowjob techniques she researched on the internet, but there's no way I'd be addicted to her blowjobs... - At first it was meant to be 'practice', but before I knew it, I was being licked and fucked...!