Let's take a look at some things, we've got a teenage boy who is not only in his own body, but in the body of a teenage girl he likes, who is attracted to him as well, and he can access her memories and personality, then there's the fact that he shares senses between the two bodies, both of which were feeling extremely horny before having sex, with the boy feeling the sensations and pleasure from both bodies at the same time with a quick recovery, and with the boy close to running on base instinct due to an urge from a power he has yet to fully understand. What do you get at that point? The pleasure from both bodies cycling through each other on a loop, making it hard for him to stop.
This is shown quite well, as despite going at it for four hours, you are unable to keep either set of hands off of the other body for any real length of time after stopping, with both bodies just trying to get as much pleasure in their hazy perception as possible.
You throw Jill's body on top of her bed on her back, by this time having both bodies completely stripped naked, and plow your penis right into her vagina, getting a moan of pleasure, and begin kneading her breasts and massaging her tits to erection as you run her hands all over your torso, and nibbling down on your neck, as both bodies are thrusting, again and again. You eventually feel a build-up in your penis, and you wrap Jill's legs around your waist, locking you in as you blast your load inside of her, causing dual screams of pleasure.
Still aroused to the point of madness, you don't stop for a moment as you have Jill's body stand up, and then press herself against a wall, squishing her breasts a little, and then press her hands against the wall, before ramming your penis straight into her butt. This causes a new wave of pain, but you instantly pull her back a little so that you can begin kneading her breasts again and nibbling on the back of her neck, causing you to let out a moan through her. You wait until her body adjusts to the intrusion before you have her bend over, hands braced against the wall, and start ramming your penis into her repeatedly, causing her body to begin crying out in pleasure.
Upon unloading again and pulling out, you have Jill's body stand up, spin around, and push your body onto the bed, before getting on, straddling your own body with hers, before lifting up, and slamming down, crotch first, on your penis, and begin bouncing up and down, with her breasts bouncing too, occasionally hitting you in Jill's face. Upon the next unloading, you remove your vagina from your penis, and readjust your bodies, with your penis in Jill's face, and your vagina in your original face, you go to town, taking all of your penis into Jill's mouth, giving yourself a blowjob, as you begin eating your female body out.
At this point, you're so lost in pleasure, that you can only think of increasing it, so you come to a simple decision. "Must... have... more... girls..." You moan through both bodies, although with your mouths full, you aren't able to do more than stimulate your penis and vagina, causing you to increase your paces on both. You separate part of yourself without thinking about it, and break it into three parts, which head to places you know girls are at, one going towards the local pool, as Anna and Rose are swimming there at the moment, although your stepmother will arriving to pick them up shortly, after having picked up Megan, with Rose staying the night, one going towards your house, and the remaining one goes towards Katherine's mansion.
What part do you focus on? Note, Andy is staying the night at a friend's house, and your dad has gone out for his military training, leaving no other male at the house. Also, by the time you come to your senses, all of the girls staying at your house will have been possessed.