Good son: walk right next to your sister´s face
From Create Your Own Story
You grab your dick and start jerking while slowly walking towards your sister. She is still lying on her back getting her pussy licked. But she doesn´t pay any attention to Angela anymore. She is just staring at your penis now. You are standing right next to the bed now and jerk your penis a few inches over her face.
"This is just too weird!" Siri says all of a sudden. "I mean... we both like you. So... you gotta pick one of us. It´s not like we can all be doing it!"
"Why not?" Angela says. "I mean... we have been doing it, right Siri? And we both like your brother, so there shouldn´t be a problem!"
"What do you think big bro?" Siri asks. "Do you want to only have sex with Angela or do you want to take us both?"