I recommend that you read chapter 1, 2 and 3 before delving into chapter 4, but here is a quick recap reminder of what happened. Eighteen year old Kevin Lansing came home to find his older sister Hannah licking his twin sister Kristen's hot pussy. He quickly stripped down and joined in on the filthy fun, where plenty of licking, sucking, tonguing and fucking took place. Later, their mother Krystal, a dominant mistress, and father Kevin, a submissive pet, came home and the fun continued. After some punishment was served to Hannah, Krystal devised a blowjob contest between the sisters. The losers of the contest were placed into a diabolical bondage for the evening in a room called 'the doghouse', while the winners are about to enjoy the delights of victory.
Chapter 4 - It's going to be a long night...
It was only a few minutes into Kevin and Kristen's night in the doghouse, when Kristen realized that she had made a bad mistake. As water from the enema bag flowed into her bowels, a new need suddenly made itself known. "Kevin?," she called out.
"What?"
"I can't see your face, where is it?"
"Same place as always, attached to the front of my head," he quipped wryly.
"No silly, I mean where about is your face? Are you right underneath my pussy?"
"Yeah sis, I can smell you, but I can't-" he stuck his tongue out as far as he could and tried to lift his head, but only managed to barely touch the fleshy part of her labia with maximum stress. "Ahh, I just can't reach you."
"But you're directly below me?"
"Yess," he hissed, starting to become annoyed with her questions. He was also struggling to resist the steady pump of the machine on his cock. The need to cum was starting to build already.
"I think we may have a problem," Kristen said in a low voice.
"What? Speak up, the machine is too loud."
"I said, I think we may have a problem," she repeated in a much louder voice.
"What problem?"
"I have to piss."
"What!?!" Kevin snapped, suddenly very anxious. "Why didn't you go after supper?"
"I went just before supper, and I didn't have to go when we finished. I didn't know that I was going to be suspended over your face Kevin. This stupid enema is filling my gut and putting so much pressure on my bladder, plus I drank two tall glasses of wine, and that's not helping."
"Well, you need to hold it sis. You can't pee now, you'll piss all over my face."
"I know, but I can't see how much more water is in the enema bag. It's still running into me though, and it doesn't feel like it's slowing down. There's no way I'm going to be able to hold it much longer."
"Shit!" Kevin cussed, then yelled, "Hey...Mom, Dad, Kristen's gotta piss!"
"They're not gonna hear you Kevin."
"I know," he grumbled, "Damn it Kris, I can't believe this."
"Hey, some people like to get pissed on. Maybe you'll like it too," Kristen reasoned.
Kevin sighed loudly. The machine had picked up speed and his orgasm was approaching faster than he wanted it to. For some unknown reason, the talk about him getting pissed on was somehow making him even hornier. Why, he didn't know, but he wasn't about to admit it.
Kristen held out for another few minutes. As the bag emptied the last of its contents down the hose and into her bowels, a new surprise awaited Kristen. "Unnahh oh shit, it's vibrating!"
"What's vibrating?"
"Ohhh ffuuck, the dildo in my ass just started buzzing away. I'm so fucking full, and now this thing is... oohhh sshhiittt, I'm cramping again. I'm gonna pee Kevin!"
"Kris, it's okay. I forgive-" Kevin began, but was interrupted by his sister's frantic wail.
"Ahhh I can't hold it anymore," she said, gritting her teeth as another cramp started, "I'm sorry Kevin."
Staring up into his twin sister's sexy bald pussy, Kevin saw the first few dribbles of yellow liquid leak out from her feminine folds and drip down onto his lips. The smell of her urine was strong, and he squinted his eyes as a larger squirt come out with more force. He licked his lips, tasting the stinging bitterness, and was surprised that it wasn't as bad as he thought it would be.
"Ahhhhh!" Kristen yelled as she finally gave out and released the flood.
The scalding hot spray blasted Kevin, and he closed his eyes tightly as his whole face was covered. Once Kristen started pissing, the relief was so great that she pushed forcefully to empty her bladder as quickly as possible. Kevin couldn't believe how much piss was spraying out of his sister and how fast it was coming out.
Then, to make matters worse, just when her spray got overwhelming, he started to cum.
"Mmmmhhh!" Kevin moaned, trying to turn his face away from the stinging hot spray, while his orgasm racked his body with spasms of pleasure. The sucking tube was relentless, still stroking at a high rate of speed because his semen hadn't reached the reservoir yet. His body moved of its own accord attempting to thrust his cock forward, but the straps held him tightly. His sisters piss stream weakened about the same time that his cock became super sensitive. Luckily, his semen reached the resevior and the sensors dialed down the suction, slowing the tube and, at least momentarily giving him some minor relief.
As the last few drops of pee dripped from Kristen's pussy onto Kevin's lips, he heard her low voice call, "Kevin?"
"Yeah?"
"You alright?"
"Yeah... How about you?"
"I don't have to pee anymore."
Kevin chuckled and nodded, "That's good." He felt his cock starting to shrink in the tube, but before it was flaccid enough to fall out, the suction picked up, and soon he was fully erect all over again.
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