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Stiles and Derek were best friends, had been since they were in diapers. Their parents were friends, so they were around each other more often than not. By the time they started school, they only wanting to play with the other. It got so bad, their kindergarten teacher forced them to play with the others, just so they socialized with others. They did from time to time, just so they wouldn't get in trouble, but they preferred doing things together. If you saw one, you'd most likely find the other right next to him.
At their kindergarten graduation, the two boys begged their parents for a weekend long sleepover, not knowing if they would see each other during the summer break. Their parents chuckled, knowing the two would be seeing each other every day but still agreed.
The only problem was that the Stilinskis had to go out of town for a family wedding and the Hales had a business meeting that was also out of town. Normally, they'd ask Scott's mom to host but she was working double shifts since Scott would be with his dad all summer long.
It was actually looking like the pair would be separated briefly that summer. But thankfully, Derek's uncle volunteered to watch the boys for the weekend. He usually worked during the week so he was free to watch the boys on the weekend. The adults agreed, especially with all the begging from their sons, allowing Peter to watch them.
Peter was going to watch them at his apartment, something the boys loved since it was somewhere new to explore. Being the fun uncle, he ordered pizza and bought a lot of junk food and let them watch whatever movies they wanted. The boys had so much fun watching movie after movie all while gorging themselves on pizza junk food, and soda. By the time they'd usually be going to sleep, Stiles and Derek were too hyper. By the time their latest movie ended, the boys wanted to watch more but Peter wasn't there anymore. They went from room to room searching for him until they heard a noise coming from Peter's bedroom. Slowly, they made their way to the closed door, Derek hiding behind the braver Stiles, and carefully opened the door.
The sight that greeted them was Peter on his bed, naked from the waist down, with his legs spread wide open. The man's fingers were in his hole, stretching it wide. Neither of them had ever seen anything like that before, only seeing themselves, and each other, naked. Opening his eyes, Peter saw the boys watching him from the doorway, mouths hanging open.
"Sorry, boys," he panted, not sounding sorry at all, "I thought I could do this before your movie ended."
"What are you doing Uncle Peter?" Derek innocently asked.
"Why were you playing with your butt?" Stiles added. "And why do you have your fingers up there?"
"Because it feels good, boys. Ever seen someone do something like this?" He answered, sliding his fingers in and out.
Stiles shook his head while his best friend blushed. "I saw Laura do that once." Peter looked at his nephew in interest. "She doesn't know I saw. She was making a lot of noise like Uncle Peter."
"What was she doing?" Stiles was very curious. "Why's your thing getting bigger, Peter?"
Peter smirked as he continued to finger himself, waving his cock like a carrot on a string. "Want to find out?" He asked. The boys looked at each other before nodding. "Then climb onto my bed and I can teach you."
They hurriedly climbed onto the bed, one on each side of the older man. Peter's legs were spread as he added another finger to the mix, throwing his head back to moan. It was a dream come true, he'd been interested in teaching his nephew the joys of sex but hadn't had the chance, especially since Derek was always with Stiles. But being able to have both boys at the same time was even better. His cock was starting to leak at what he had planned.
"Who wants to finger me?" He asked. Both of them raised their hands like it was school. "I see that you're both eager. How about you take turns. Let's have Derek go first. Don't pout, Stiles. Next activity you'll get to go first. Derek, get between my legs and stick your fingers inside my hole." Like an obedient puppy, Derek scrambled to get where he was told, sticking one of his fingers after his uncle pulled his out. "Try three, nephew." Peter encouraged. Pulling his one out, Derek stuck his middle three fingers into the hole. It felt a little tight but he was able to move them around too. He stayed like that for a bit, wiggling his fingers inside his Uncle Peter's hole.
"Can I have a try?" Stiles asked, forever impatient.
"Go on," Peter smiled, letting the boy join his friend.
He didn't wait too long before Derek had removed his fingers before he shoved his in. Stiles was more enthusiastic about doing something naughty, loving the fact that he had his fingers somewhere he probably wasn't supposed to. He wiggled his fingers too, alternating between which fingers were inside. He then added another to the equation, making it four of his little fingers.
"Try getting your whole hand in," Peter panted out. He was loving the attention those boys were giving him.
Stiles slipped his fingers out before making a little fist and pushing in. It was more difficult to get it in than just his fingers but that didn't stop him from pushing forward. Peter had to grab the boy's hand and shape it into a way that would be easier, forcing his fingers together and creating a point. The new hand shape was much easier, sliding in easily and smoothly. Peter threw his head back and moaned, the mental image of being fisted by such a young boy almost made him cum.
"Can I do that too, Uncle Peter?" Derek sweetly asked.
"Go ahead," Peter moaned.
Instead of feeling one hand pull out and another in, Peter felt a stretch he'd never experienced before. Looking down, his eyes widened as he saw his sweet nephew narrow his fingers like his friend's and was pushing into Peter's hole. He was about to stop Derek, but before he knew it Derek's small hand joined Stiles's.
"Aw, fuck," Peter fell back onto his pillows. The boys giggled at the curse word.
With two little hands inside his hole, Peter's cock was leaking so much precum, it was starting to soak into his pubes.
"What's that, Peter?" Stiles asked, touching the dripping and twitching cock.
"It's called precum. How about you boys have a taste as see if you like it."
As they moved closer, their still sheathed hands stretched out the hole more, causing more precum to dribble out. The boys gave the cock small licks, tasting the new thing. From their first taste, Stiles and Derek couldn't get enough, trying to get as much precum as they could. The sight of the two boys gobbling up his pre made Peter cum, a few shots shooting in the air while the rest dribbled out of the twitching cock. With something new to taste, the boys greedily took as much as they could. In the end, Peter's cock was clean, although it was wet with boy spit.
"Have your fill?" Peter asked when he wasn't panting anymore.
"Yeah," Derek was a little embarrassed with how he acted with the cum.
"Uh-huh," Stiles answered, licking his lips for the last taste.
"Now with that out of the way, I think I promised you boys how having fingers inside your ass feels like." Both boys were excited. "First, I need you two to take off all of your clothes." They stripped quickly, Stiles getting his head stuck while taking off his shirt. Fully naked, Peter admired their young bodies and could see their hard little dicks. Derek's was a little bit bigger but he was a Hale and their family was known for having big cocks. "Ok, now I want you to lay down like I was, pull up your legs so I can see your holes." They did as they were told. "I'm going to pour some lube on you so it won't hurt as much."
"Are you going to put your hands in us too?" Stiles asked.
Peter chuckled. "No. But let's start with one finger and see how you like it."
With the holes lubed, Peter ran a finger on each hand down to get started. He gently pushed in, taking his time so he didn't scare them off playing with their holes again. Every so often he'd have to slow down or completely stop to allow the boys time to adjust to the new sensation. By the time he had a finger completely inside each boy, they were both already panting like dogs in heat. Looking down at them, Peter could visualize what it would look like when he eventually did fist them. The vision alone made his cock get hard again. Moving his fingers back and forth, Peter could see that they were already close. They were both too young to cum like him but that didn't mean he couldn't get them to have a dry orgasm. Hooking both of his fingers, Peter was easily able to locate their underdeveloped prostates and stimulate them to completion. Both boys shook and opened their mouths for silent screams as they experienced their first orgasms. Peter's cock was dripping precum again.
"Uncle Peter?" Derek asked when he had regained control of his body again. "Can you always babysit me?"
"Yeah, can you babysit us all the time?"
"Let's get through the weekend first," Peter grinned, "then we can see about doing this more."