"What the hell!?" she shouted, rather shocked to find herself half naked, lying on top of her rather petrified looking twin brother, quickly jerking back onto her knees. "What the fuck Tim? What's going on?"
"Nuh-nothing! I wasn't doing anything!" you nervously told her, praying that she wouldn't notice your still hard cock, now pressed up against her leg, letting out a little gulp as you did.
"Then why the hell am I in your room?" she continued, appearing rather confused and disorientated as she gazed angrily around your room, presumably expecting to find Jimmy somewhere in a corner snickering away to himself over whatever prank it was she’d assumed you'd pulled.
Desperately seeking a way out of this situation, well aware of how bad this looked and how much shit you'd get off your mom if she thought you'd been doing stuff with your own sister, you quickly went on the defensive, blurting out the first thing that came into your head. "You, uh...you were sleepwalking!"
"Sleepwalking? What do you mean sleepwalking?" Heather began with some skepticism in her voice, as she pulled the rest of her body from off yours, inadvertently pressing your erection further into her leg in the process, causing her to pause. "What the...?" Instantly you froze as her eyes dropped down towards your crotch, a look of revulsion appearing across her face as she finally realized what it was, her reaction causing you to curse Jimmy silently in your head.
"Oh my God! Tim, you pervert!" she shrieked in horror, jumping from the bed and covering her underwear clad body with her arms. "You've got a fucking hard on! Eww, that's so... so gross!"
Unencumbered now from your sister's body, you quickly pull yourself up onto your knees, hiding the slowly deflating tent in your jeans from view (your aroused state having now completely dissipated), and take the defensive. "Well...what the hell are you doing wandering into my room in your fucking underwear and jumping on top of me in the first fucking place?" you faux-angrily shouted, trying your best to turn the tables in your favor (as well as cover up some of your obvious embarrassment), "Wait till mom hears you were trying to molest me."
"Molest you...? I wuh...I wasn’t..." Heather suddenly stammered, slightly taken aback by the accusation, "What the hell are you talking about? I was in bed fast asleep!"
"Well then you must have be trying to molest me in your sleep or something ‘cause that's what fucking happened!"
"Why the hell would I want to molest you, you little rat? That's so sick! This has got to be some stupid pervy game of yours and Jimmy's!"
"No it it's not, Jimmy's not even here! He uh, he went to the bathroom like 5 minutes ago..." you lied, glancing back up at the ceiling again for a moment, wondering if he was indeed still up there watching you. Looking back at you sister's puzzled face, her confused expression suggesting that she was perhaps, ever so slightly, actually starting to believe your lies, you then decided not to chance you luck any further and hastily told her, "Now get out of my room! I was trying to get to bed before you fucking interrupted me!"
Letting out a angry little snort and folding her arms in front of her chest, Heather then sneered, "Whatever!" before turning and stomping her way back out of your room and across the hall, slamming her own bedroom door behind her.
"Phew, that was lucky," you said to yourself, wiping your brow and gazing back down at your now (thankfully deflated penis), "I just hope she buys the sleepwalking thing and doesn't tell mom or I’m in deep shit." It was just then however, after closing the door and looking back around at your empty room that your attention turned back to your ghostly best friend, who was no doubt laughing his ass off. "Alright you dick, you can come out now!" you said, your relief turning to anger again as you waited for Jimmy to reappear, "I bet you thought that was hilarious didn't you, trying to make me look like a perv in front of my sister? Well the joke’s over!"
"You've got to admit, that was pretty darn funny though," a voice from behind suddenly spoke, causing you to jump slightly as you turned to see your best friend's giggling face as he casually sat back down onto your bed, seemingly wiping a little tear from the corner of his eye.
After getting over the weirdness of him re-materializing out of nowhere for a second (still feeling a little unnerved seeing his powers in action), you then sprung at Jimmy in a rage, pushing him hard in the chest and knocking him backwards fully onto the bed.
"No, it wasn't fucking funny, you ass!" you told him crossly, not amused in the slightest by his actions, "She's my fucking sister for God's sake! And now she probably thinks I'm some weirdo pervert that was touching her up!"
"Hey dude, c'mon, don't take it so seriously," Jimmy responded, still chuckling away, shielding himself from another blow with his hands, "I was just messing around," and adding with a cheeky little grin, "And besides, you kind of were touching her up as I recall..."
This comment stopped you in your tracks, and you tried to stutter out something in response, "I...wuh...I wasn't...uh..." but failed miserably as you ceased your attack on Jimmy's body and instead just slumped down beside him on the bed, your face turning red with guilt at having felt up your own sister's breasts. While you had to admit that Heather did have quite a nice looking body (and especially a nice set of tits) and it had been, in a roundabout sort of way, your idea for Jimmy to possess someone in your family, you couldn't help but feel slightly ashamed at having gotten turned on by her laying half naked on top of you, not to mention knowingly groping away at her boobs.
Jimmy meanwhile, continued giggling away to himself as he sat back up and gave you a playful little tap on the shoulder, still wearing that same cheeky little smile on his face. "Heh-heh, I knew you couldn't complain about that part; your sister is well hot! And did you see those cute little lacy panties she was wearing? Man, I totally should have taken them off first..."
"Fuck sake, Jimmy, that's my sister, man!" you spoke up once again, getting your nerve back and cutting him off mid stream.
" I didn't hear you complaining when you were giving her melons a good old squeeze."
You really wanted to chastise your friend further for this, but you didn’t exactly have the moral high ground, nor were you really in the best position to either; what with him being the one with the amazing possession power, a power that meant he could become anyone he wanted anytime he wanted, including you (which he could well do if you didn't stay on his good side. And so, not wanting to rock the boat any further, you instead just mumbled rather weakly, "Yeah, well...it's not right..." before deciding it best to just call it a night, hoping you might feel a little less embarrassed in the morning, as well as, in a weird, selfish sort of way, secretly hoping that Jimmy might perhaps want to do the same sort of thing tomorrow, only this time hopefully with someone who wasn't your sister.
Eventually however, Jimmy did apologize while you both got changed and ready for bed, sensing that you were still a little upset with him (though clearly still finding it rather funny himself), and as you climbed under the covers and him into his sleeping bag, he flashed you a rather devilish smile, and reassured you, "Don't worry, Tim, dude, I'll make it up to you. Just you wait and see..."