HEYZO-2059 When he went to his girlfriend's house to play, the boy was invited to have sex with his sister

The story is that that day I went to visit my girlfriend. Unfortunately, she hadn't returned from her part-time job yet, so my sister Rino Sakuragi replaced my girlfriend to drink beer and chat. While I was busy looking at Rino's plump breasts and her sexy face, she suddenly pulled down her bra and stared at me with wet eyes. Before she was surprised, she grabbed my penis. my cock in my hand and sucking it deliciously. I don't want to do anything wrong to my girlfriend, but the temptations coming from her sister are something I can't refuse.