This is one of my favorites. ( I'm a sucker for a common sense change plot). In this video being tired of your sister being a bitch to you. Even yelling at you for checking her out in the shower! It's her fault for faulting her body like that. You buy a sketchy powdered drink mix off the internet. Called Free use juice. It's promises to have your sister leave the towel on the floor and start being your whore. So when you see your sister is hanging out with her boyfriend watching a movie you give her some , what happens next makes the boyfriend made enough he storms out, later when you see he's video calling your sister again you figure you might as well "help" him understand this all a misunderstanding because just like your sister tells him " Dude, chill out, why are you freaking out? It's common sense to have your sister gag on her brothers cock. Just like its common sense to let her brother fill his sister with cum any time he wants." He doesn't seem to get it so you show him. ... Wait what?! Your sister says she didnt drink the last shake you made her?! Oh man, I hope your mom doesn't drink the extra your sister left in the fridge?! Wait, how long does this last and when was the last time your sister had some?!