High school senior Eric cares for his sister more than anyone in the world. He wants her to be happy. One day he overhears his sister talking to her friend. His sister is feeling a little lonely and is feeling pressured into giving up her virginity to a guy she doesn't love. She has been fighting the matter but she has finally decided to give up her virginity to the guy. Eric is desperate to help his sister he tried to talk to his sister but he couldn't figure a way to talk her out of it without letting her know he had been listening in on her conversation.
Eric goes up to the attic where some of his Grandmother's stuff has been stored. It was rumored that his grandma had been a witch or something. It took him a couple hours to find an item that would work. He found a doll that would let him control his sister.
Eric is able to set up the doll to be able to control his sister whenever she is feeling the urge to give up her virginity to someone she doesn't love.
When he tries to use the doll it doesn't seem to work. Then he lies down on his bed and falls asleep, even though it is the middle of the day. When he wakes up he is in his sister's body. He is worried because this isn't how the doll was supposed to work.
While in his sister's body he sees that she is walking up to the door of her boyfriend's house. The boyfriend smiles and welcomes her in. The boyfriend asks if she's decided if she's finally going to sleep with him. He asks in a way that really ticks off Eric. Eric can feel that his sister is about to say yes but she also doesn't want to and she doesn't love the guy.
That is when Eric feels his control take over. He says no to the sex but it comes out his sister's mouth in a way she would say it. Eric feels his sister's surprise at saying no. But more importantly he feels her relief. Her boyfriend tries to talk her into sex but when he realizes he's not going to get any he breaks up with her, calling her different names. The boyfriend then reveals he'll get some from her friend like he always does whenever she says no. It's the same friend that Eric heard his sister talking to about having sex with this jerk.
Eric stops his sister from having sex a few times. Each time he is a passanger in her mind. It surprises Eric with some of the guys she is tempted to give her virginity to. Especially one of their teachers and their own Dad.
During one point the sister figures out that her brother is controling her when she is tempted to have sex. And she is mad at first but is really happy when she figures out the reason for him doing so.
They talk things out about the control thing and she gives him permission to continue doing this until she has found someone to give her virginity to that she truly loves.
One night Eric wakes up to a wonderful feeling. He belives that he is still dreaming. But then he realizes his sister is giving him a blow job.
He asks what was going on. She replies that she is thanking him for all he has done for her. He wonders aloud why the doll didn't let him take control. She laughs and says that this isn't exactly sex. The doll must have only helped him stop her when it came to vaginal sex. And before Eric asks she tells him it has only stopped her from having vaginal sex because she has been giving a few blow jobs.
He tries to find out who she has given blowjobs to but she laughs again and moves up his body. She holds onto his dick and says that this is an early graduation gift.
As his dick presses it's tip next to her entrance Eric feels the pull of the doll. He is once again inside his sister's mind. He feels the love his sister feels for him and the need she has to become one with him. While they make love he is back in his body. But once they both know they are going to have their own orgasms he feels the pull of the doll once again and learns that one reason his sister is wanting sex now with him is so that she can have his baby.