Offline/Help Emma pick her body clean
"Yeah, there is a lot. Can I help?" you offer. Emma shrugs. Good enough. You crawl out of your bag which is when you realize you're naked. That's not normally strange, but you've been trying to sleep in your boxers due to your sister. Drunk you must not have been thinking about that last night. Thankfully the short distance between the two sleeping bags is littered with Emma's clothes. You're not going to put them on, but you carefully place your dick on one of her discarded articles as you lay prone so that your dick isn't squished against the wood floor as you stretch out to get closer to your sister.
You feel like you need to apologize over and over, but you sort of don't want to either. Covering your sister in your cum is the hottest thing you've ever done in your life, and you're weirdly almost proud of it. So you mostly bite your tongue, the two of you silently pick at her body together, Emma focusing on her stomach while you gently scratch at her neck. You keep managing to tickle her, unintentionally you swear, but you can't get under her chin while she's doubled over trying to scan her body.
"Tilt your head and I won't tickle you," you tell her.
"Then I can't see."
"You can't see anything anyway." You reach down and flick a small white flake off of her belly. "Here, just lay down and let me do it. I can get you cleaned up."
Emma thinks about it for a second then spins her legs back onto her sleeping bag and drops her head onto her pillow. What she doesn't do is remove the one hand covering her crotch, but she does lay the other beside her out of your way.
After moving forward a little you get back to attending to your sister's neck. A bunch of little translucent white splatters are all over her shoulders and chest, along with some scattered bits at the base of her neck and at least one little trickle that spilled down over the side of her jaw. You diligently pick at your own dried cum, manipulating her head this way and that in the process, if only to prove you're being thorough.
Once it looks good you move up to pick at her face. Emma is amused by this, having you hovering inches away and touching every crook and cranny of her young features. She probably has a mirror or something so she could do this part herself, but she's entertained enough to let you try. You're forced to gently scratch along one of her eyelashes, to lick your thumb and rub out her eyebrows, and do all sorts of weird things to remove your crusty spunk. She tries to turn her smile into a frown and keeps looking away from you, eventually making herself giggle more than once.
"What? Does it tickle?" you ask while you scratch the side of her nose. She just shakes her head.
Once you're done with her face you move lower. You reach across her shoulders and remove the flecks that pepper them, only to find your arms tiring in this position. So you get up off the floor, sitting up on your knees and tucking your feet under your butt so you can more easily lean forward over your sister. This also reveals your stiffy which is happy to bob up into the air after being trapped below you for several minutes. Your sister definitely notices but doesn't say anything.
Moving to Emma's chest there are some obvious blotches and long running streaks that need to be taken care of. You remove one right in the center of her flat chest, scraping away the bulk of it then gently rubbing your thumb up and down from her sternum to her collar bone, the outstretched fingers on your hand repeatedly grazing her far nipple. That too feels crusty, so you attend to it as well, rubbing around it in a tight circle to help flake off your jizz.
You lifted your butt off of your feet to help stretch forward and reach Emma's far nipple, making your erect dick that much more prominent. Emma has already been glancing at your junk as you take your time to rub down her chest, but with it floating out in front of you she can't keep from commenting.
"It's hard again, isn't it?"
"Yeah, thanks for that," you reply with a chuckle.
"For what?"
"For making me hard."
Emma's brow furrows. "I didn't do that."
"Kinda, yeah," you nod while lightly flicking at her nip with your fingertip, just to make sure. "Seeing naked girls usually gets it hard."
"Really?" Em glances up and down between you, your cock, and your hands, processing this information. "Even your sister?" she asks skeptically. You shrug.
"I dunno how it works, not really. You can make it hard by rubbing it, but sometimes it just likes what it sees. And right now I can see you're naked. Dicks are real honest like that."
Emma scowls at you for a moment, trying to decide how honest you are being, then looks down at the finger still on her nipple. You pull off, give your thumb a quick lick, and then plant it on her chest rubbing her bright pink dime for a few more drawn out seconds and stiffening it up a little before deciding to move on. She watches your fingers rub their way to the other side of her chest, and glances over at your cock a few more times. Then she tilts her head back to stare up at the ceiling, seemingly to get more comfortable. But slowly, haltingly, she drags her cupped hand away from her crotch, over her hip, then drops it to her sleeping bag, voluntarily exposing her entire body to you.
She tried to be stealthy about it, as if she didn't even mean to uncover herself, or not draw your attention to it, but her intention is pretty obvious. If she didn't want you to get hard she'd try to cover up more, but instead she revealed more of herself, opened up her entire naked body to you. She licks and purses her lips, pretending not to look at her equally naked brother as you rub and knead the second half of her bare chest.
"This stuff is so hard to see," you declare as you sweep one of your hands down onto her small stomach. "Really is easier to feel for it." Gentle but firm, you rub and glide over her skin, your two hands synchronized as you caress and explore her body in smooth sweeping circles.
"Yeah," Em says with a shaky breath, her eyes focused on a particularly uninteresting spot on the roof, her cheeks starting to blush.
Surprisingly, you really enjoy touching your sister's body, even just skin to skin contact. You didn't exactly start this with virtuous intentions but past all the nipple flicking and invasiveness trying to embarrass or rile up your sister, it's strangely satisfying to glide your hands down Emma's sides, up her chest to the base of her neck, or to circle your fingers around the edge of her belly button. You do find the odd little flake that you scratch away, but this has become less about the task and more about the journey, and it's a journey your sister appears to also be enjoying.
You reach up to Emma's chin again, gripping her small neck in your hand briefly then run the back of your fingers up her jawline and over her ear. Her eyelids flutter slightly when you trace the outside of her earlobe. You loiter here for a while, playing with her hair, softly rubbing her temple, before moving back to her body. You stiffen her tiny nipples again, just because you can, then sweep your fingers back and forth across her chest.
When you gripped your sister's neck you placed your other hand below her belly button. It drifted a little, definitely below her pantie line, but you never tried to go lower. You just wanted to let her know you were in the neighborhood. But when both of your hands dip below her belly button you can tell she gets nervous. After rubbing across Em's pelvis a few times, skirting past the edge of her slit, you slide your hands onto the tops of her thighs and find the odd like fleck here and there. But you've definitely run out of new spots to check. There's only one place for you to go now. Dipping one hand to the inside of her thigh, you drift upward until you make contact with her pussy.
That sure gets her attention. Even if she was waiting this entire time to see if it would happen, she wasn't entirely ready for it once it did. One of her legs lifts a little and her head pulls up off her pillow. Both of you freeze, your sibling drawing in a deep breath.
"Sorry. Should I check?"
Emma licks her lips again, sucks them in, then nods. Both of you watch intently as you rub your fingers along her soft rounded vulva. Up and down, carefully, repeatedly, stopping to run a tight circle at the top of her slit, only to push back down a moment later to follow that small cleft underneath her again.
You look up at Em and notice her nostrils flare a little with a deep breath in as your hand stays focused on her pussy. Her cheeks are quite pink now. She tries to meet your gaze but can't keep it, forced to look away out of embarrassment, or worse. You keep it up just a little longer, willing to do anything that makes her feel good, before you decide you can't push the charade any further and declare her officially finished.
"Alright, I think you're good."
Emma bites her lip, nodding in agreement, and lifts herself up onto her elbows. Once you pull your hand away you rise up onto your knees, straightening your body and flexing your arms. You also push your hips forward, hanging the profile of your stiff strained cock out in front of your little sister's face.
"Are we both, um... good?" she asks.