Chapter 1: Shower
Before he even knocked on the door, Katsuki could hear the commotion in the Midoriya apartment. Inko, mother of his charge, was fussing and fretting over leaving her six-year-old for the weekend, even if it was with his trusted babysitter.
Katsuki smirked, anticipation tingling in his fingertips at the thought of having Deku to himself for the whole weekend. He'd been babysitting the kid for just over a year, and he knew he was the boy's favourite person. Just as little Deku was his.
During the year he'd babysat Deku, he'd occasionally watch him overnight, but mostly for an afternoon or evening. And Katsuki enjoyed those stints, but this, a whole two days of just them, well, he could hardly contain himself.
He knocked, the fretting on the other side of the door quieted before a joyful squeal shrieked through. The door swung open, and Katsuki had a pair of small arms wrapped around his thighs.
"Kacchan!" Deku hugged his babysitter tight, pressing his face against the teen's crotch as Katsuki tried not to get flustered.
"Hey, Deku," he replied, ruffling the kid's hair. "You miss me?"
"Yeah!" Deku pulled away and beamed up at Katsuki. "It's been forever!"
"It's been two weeks," Katsuki chuckled, taking the boy's hand and leading him back into the apartment. "And why are you still in your PJs? Didn't I tell ya to be ready?"
"Oh, Sorry, Katsuki," Inko Midoriya said, approaching them with her suitcase rolling behind her. "I completely forgot, it was just such a rush this morning,"
"Don't worry about it," he replied, shooting the woman with a smile. "I'll take care of everything; don't you worry one bit." He looked down at Deku. "Say goodbye to your mom and tell her you'll be good."
Deku did exactly that, darting to his mother and hugging her tight. She returned the embrace.
"I'll be the best boy for Kacchan, I promise!" the boy declared, fists balled in front of his chest.
"I know you'll be," Inko cupped her son's cheek. "But remember, do as you're told, eat what's put in front of you, and don't be naughty."
"He never is, Ms. Midoriya," Katsuki chimed in, ruffling Deku's hair again. The mother smiled at him, said the last goodbyes to them both, and left.
"Well, now it's just us boys," Katsuki said, kneeling to Deku's level and looking him in the eye.
"Yeah! Just us boys," Deku agreed, bouncing on the spot.
"First thing's first, you need a shower, stinky." Katsuki pinched his nose and turned away in faux disgust. Deku pouted and gripped the hem of his pyjama shirt.
"C'mon, let's get this done." Katsuki winked at the boy and led him by the hand into his bedroom. He sat on the edge of Deku's bed and pulled him between his legs. "Arms up," he said, and Deku obeyed.
Katsuki lifted the boy's shirt over his head and tossed it into his wash basket. His eyes trailed down the boy's bare torso, all the way down to the hem of his shorts. And out of that waistband he saw the tell-tale white tab of a pull-up. He kept his smirk to himself.
"Now these," he said as he tugged the shorts down and let them fall to Deku's ankles, leaving him in just his pull-up. Deku blushed and looked away.
"I've told you not to be embarrassed, Deku," Katsuki said, poking the boy's forehead. "You need 'em, no two ways about it. Besides," he leaned in, rested his hands on the boy's hips and whispered in his ear. "I think you look fucking adorable in them."
"Kacchan!" Deku gasped and put his fingers to his lips. "You shouldn't say bad words, it's not nice," the boy decried, though he was unable to hide his own smirk.
"But I like it," Katsuki growled, running his fingers over the boy's hips, forcing Deku to giggle in a fit of tickles. "Almost as much as I like you."
Deku giggled again, and a flutter of butterflies flourished in Katsuki's chest.
"But, important question, are you dry?" Without waiting for an answer, Katsuki pulled the front of Deku's garb out and peered in. Katsuki felt an instant pulse in his jeans, his member throbbing the second he saw Deku's bald little prick. He swallowed to stop himself from drooling.
"Looks like you are," Katsuki said, smiling at the blushing boy as he took his phone out, aimed it inside the pull-up and snapped a photo.
"Kacchan," Deku pouted, his blush turning to a full facial flush.
"What? I told you I'd be taking pictures. And this isn't gonna be the last picture of your cute lil' dick I take," Katsuki said with a smirk. Deku could only look away, his blush creeping down his neck.
Katsuki then hooked his thumbs into Deku's pull-up and yanked it down to his ankles, leaving the boy as naked as the day he was born. Deku brought his hands down to cover himself but a tickle to his armpits had him giggling and showing off again.
"Oh yeah, here he is, "Katsuki said, holding each of Deku's hands in his own and pulling him in close. He leaned in, pressed his lips to the naked boy's, and moaned, his cock straining.
Deku mewled into the kiss, keeping his eyes closed, feeling a hotness trickle through his body. His Kacchan's hands drifting down his sides and to his hips, and cupping around to his bare bottom, didn't help the situation.
"Right, this isn't getting you ready to go out, is it?" Katsuki asked after pulling out of the kiss with a pop.
Deku, flushed and breathless, could only nod. His blush only intensified when Katsuki took another picture of him, showing him naked from head to toe.
"Now turn around," Katsuki asked, phone still trained on Deku. With a groan, the boy did as a told, and turned around, showing his naked cheeks to his babysitter.
"Oh yeah, that's a good boy," Katsuki praised, taking a few pictures before switching to recording. He reached out, caressed Deku's right cheek and pulled it aside, showing the boy's hole to the camera. It winked, and the cheek bounced back into place.
"C'mon, let's go," Katsuki said, saving the video and standing. He led Deku into the bathroom, turned on the shower and lifted him in when it was warm.
Katsuki ran his hands all over Deku's naked body, coating him in a lather before rinsing it away, he massaged shampoo into his scalp and when it came time to wash it away too, Katsuki had his camera aimed at him again.
"You're so fuckin' sexy, Deku," Katsuki said as he caressed down his back and to his bare bottom. "I think I have that problem again," he continued, squeezing the boy's plump cheek. "Wanna help me out again?"
Deku turned on the spot and, with bright eyes, nodded up at Katsuki. "Hell yeah!"
Katsuki barked a laugh at the boy's curse, unsure whether to be proud or not that he was rubbing off on him.
"Good boy." The teen set his phone aside, undid his jeans and slid them down, his rock-hard cock tenting his boxers. He pushed them down too, and finally, his cock was free.
"Whoa," Deku said in a low whisper, feeling that hot tingling spark in his tummy upon seeing Kacchan's willy.
"You'll be this big one day, probably," Katsuki affirmed. "C'mon, you know what to do," he said, guiding the boy's hand to his tip. "Oh yeah, that's the stuff."
Katsuki bit his lip when he felt Deku squeeze his cockhead, precum already starting to drizzle. Deku giggled as he ran his hand down the length of his babysitter's willy, all the way down to the patch of hair at the base and squeezed as he ran it up again.
"Oh fuck," Katsuki breathed as he felt Deku's little hand touch and stroke his member. One of his own hands went to the boy's wet locks. His hips bucked into the touch, trying to make it harder, faster.
"Kacchan gonna do a cummy?" Deku asked, bringing his other hand to Katsuki's cock and stroking again. This time faster and tighter than before.
"Fuck yeah! Fuck yeah, Deku!" Katsuki already felt the hot pulses of pleasure tremor through his dick, from the tip of head of his cock to the tips of his curling toes. Hot streaks of euphoria erupted from his boyhood, splattering all up his Deku's chest and neck. The naked boy giggled and laughed, pulled and stroked harder and harder, making the teen shoot another volley of cum, this one dribbling all over Deku's fingers.
"Fuck, shit," Katsuki panted, his knees trembling as he saw stars, his throat dry and his eyes rolled into the back of his head. "So good," he praised, just barely able to keep himself from falling back.
He managed to straighten up and looked down at his charge, his own cum coating his chest, neck and hands. He took a picture.
"You're too fuckin' good, Deku," Katsuki said as he pinched the boy's chin, tilted his head up and kissed him. This time, his tongue pressed against Deku's lips and slid its way in. He lingered for only a moment, though, before pulling away.
Katsuki righted his clothes and washed his cum off of Deku. A moment later, Katsuki was tossing the naked and wet Deku onto his bed, wrapped in a fluffy towel. The boy giggled as he bounced, and shyness towards his naked body being seen melted away.
"C'mere," Katsuki growled and grinned as he grabbed Deku by the ankles and pulled him to the edge of the bed. "Too fuckin' cute, you are," he said as he ran the towel all over him. "And you're all for me, aren't ya?"
Then, when Deku turned over onto his stomach and tried to crawl away in a fit of giggles, Katsuki took his chance and swiped his hand across the naked, bouncy cheeks. Deku yipped in surprise but nonetheless continued his struggle for freedom.
"I got you, little brat," Katsuki declared, crawling onto the bed and pulling Deku towards him, wrapping his arms around the boy and holding him close. "I win!"
"You always win," Deku said with a pout, still squirming against Katsuki's embrace.
"That's cos I'm big," Katsuki replied, flashing his teeth. "You will be too," but with that, he let Deku flop onto the bed and turned him onto his back. "But I can still give you a prize for trying so hard," he added, smirking down at the naked boy, whose little willy, after all the commotion and touch, was now standing as tall as it could.
"Y-yeah? What prize?" Deku knew what prize it would probably be, he shivered in anticipation of it, but needed to ask, just to be sure.
In response, Katsuki just smirked. He then crawled backwards off the bed, pulling Deku by the thighs with him, until the boy's rear was parked at the edge. Katsuki himself got to his knees and leaned in, his face right up against the boy's tiny stiffy.
"This prize," he answered, opening his mouth and taking in the entirety of Deku's willy and balls. Deku moaned instantly, his little fingers tangling in his babysitter's hair. Katsuki didn't waste any time either. He started to bob and suck, tightening his lips around Deku's narrow shaft and running his tongue along his length.
He pressed against his tiny tip, hand massaging Deku's thighs before sliding under him and squeezing his cheeks.
"Kacchan! Kacchan! I'm gonna, I'm gonna cummy!" Deku cried, tightening his thighs around Katsuki's head as he felt the white-hot lick of pleasure streak from his willy, shooting nothing as his balls tightened up against his body and his cocklet strained. His hips humped into Katsuki's face as he rode out the extent of his orgasm, not stopping until he felt the last ebb of pleasure seep out.
Katsuki pulled off, Deku's limp cocklet drenched in his slobber. He kissed the boy's tummy, then his chest, then his neck. He looked Deku in the eye, touched their noses together and finally pecked his lips.
"You're gonna cummy a lot this weekend, Deku," Katsuki growled into the naked boy's ear. His hands gripped Deku's ass-cheeks and pulled them apart. "You can count on that."
