Liz finds a new way to use the slide

Before Josh had any second to register what his sister just said, Liz walked right over Josh, dragging her half-erect cock along his face. Her eyes have found a new toy: the pools slide. This slide was built by their father when Liz was around 7 years old. It's placed at the edge of the pool, going up about 2 ft from the edge of the pool. It's metal body points down to the pool at an 45° angle, but with a slight concave curve. Josh turned around to see what his sister was about to do next.

"Liz, your penis is throbbing really hard right now - you're not going to cum, do you?" Josh blabbered while he used both his hands to clean his upper body from the previous precum-attack of his giantess sister.

Liz took a deep breath, her eyes staring down at the slide. "Hmmmm no. Not yet - I think?" She positioned herself right before the end of the slide, which reached up just over the height of her crotch. "I always told Dad we're not gonna use this old slide anymore and that he can get rid of it." She grabbed her dick with one hand, her touch made it grow 3-4 inches immediately. "Hmmmn Now I'm thankful he never listened to me."

With a loud THOMB her 100lbs dick landed on the curved slide, spraying precum over its entirety in less than a second, so her half-erect monster was now resting on the slide like a hotdog in a giant bun. "AHH -ah." Liz moaned painfully, as the sun did heat up the slide a lot. Ouch, that kind of hurt, she thought to herself. But that's good - my everlusting body came down just a little bit from that pain. Then she started moving.

Josh was in fear. He actually meant what he just said and seeing his 12ft muscle sister starting to smear her dick on top of their old slide made him realize: if I don't do anything now, she's going to cum and probably drain the entire neighborhood. Worse - she'll grow even bigger, taller and probably also even more horny than she already was so who knows how fast she'll want to cum AGAIN! And then again! His mind went crazy with picture of a 30 ft sister, walking through the nearby forest, felling trees left & right just by brushing them with a dick as big as their own house. He came back to his senses when he felt his own dick pushing hard against his pants. All that danger laid out - looking at her little sister with the body of a heavyweight male bodybuilder scaled up to a height of 12 ft rocking her cock against a human-sized slide was maybe one of the most arousing things he ever saw.

The god-like cock, that would put the biggest horses to shame was now sliding the sticky slide faster and faster. With every thust her cockhead seemed to reach higher & higher up the slide, now almost spilling over both sides of the slide. "Hmmm yes... Nobody has a powerful dick like little Liz." She moaned with her eyes closed right before she bit her lips, giving in to the tickling pleasure running through her fleshpole. She didn't notice how she already started to lean more forward automatically, just to create more friction between her ever-growing cock and the metal slide. While doing so, with every thrust, her gigantic ass cheeks would reach further down.

"Liz, stop right now, you're out of your mind! If you cum like this, you'll be shooting your cum like a geyser all over the neighbors houses! If you so desperately want to cum, we should do it in a more safe way!" Josh was ****.

What her brother said was probably right and she knew it. Hell - she felt so incredibly backed up by now that... she answered her brother will continuing to thrust with incredible strength. "You're right - HMMPH - Josh. If it's ok I'm just gonna - HMMPH - give it just a couple of more - HMMPH - slow thrusts, okay? I know my limit and -HAAAMMPH - I'm honestly super close to it but... you conviced me, I'm gonna - HMMPH - stop right before I cum! But hey - you had cock your entire life so maybe you know this feeling. My cock seems just about to explode and it just feels - AAAH - so fantastic - HNNNNGAAAH!!" With that last, slow thrust she now used one hand to push her dick down against the slide, raising the friction even more.

"That's called edging, Liz. Glad big brother can still teach you a thing. Haha!"

He slowly walked around her in the pool which was still drenched in Liz' precum, now alomst coming halfway up to his knees. No wonder - he thought, seeing a waterfall of sticky liquid rushing down the end of the slide constantly.

"Edging? That... HNNNGAH! Sounds pretty nice. Ok I'll be fine with just a tiny bit of edging then, Hihi" She giggled. But was that the truth? She felt that even with both her hands now pressing her cock against the slide she barely felt the slide anymore, her cock growing stronger every second. In fact, she started to push down the slide a little and instead of slowing down, she now felt like increasing the speed... just a little again. In the back of her head she knew: she needed more!

"Edging is great! I could do that all day-" Josh suddenly witnessed her sister arms wrap around the slide, right before she flexed so hard, a matrix of veins so dark and thick that it looked unhealthy crossed her mighty arms. Josh couldnt't really tell what was going on as he was still walking around his sister, almost right behind her bubbly butt.

"-all... day..." she repeated. She got back up again, the metal slide now wrapping around her cock like a metal tube. Nice, it worked! The metal is surrounding my dick completely, she thought to herself - now I can masturbate properly! Liz' was amazed by her own upper body yet again as she raised her arms only to bring them down again into a most muscular pose. "Why haven't you told me about edging before it's ... SO... Hnnngh... GREAT!" Yet she again underestimated the arousement her own muscles could give her. A loud metallic sound lead her eyes back to her other favorite muscle. Her cock expanded by her own posing & flexing to drastically, that it already started to bend the slide outwards. I guess this will need to be enough for now. She rammed her cock heavyily through the metal tube. The amount of **** she was now putting into these thrusts made the metal bend with every movement, but she didn't care anymore. As the pressure against her dick raised, so did her lust. "FUCK YEAH! Edging 24/7 only from now on... Hnngh YES!" Her eyes rolled back in her head as she was giving 10 more thrusts, each harder & faster than the last one.

Josh in the meantime was standing right behind her, an ass as big as himself jumping in front of his face. Her cheeks clapped together with every thrust, sending a spray of precum all around her like soft rain.

"I don't even need to cum, when edging is this great." She stopped thrusting for a second - then did a slow one. Josh heard metal bending, juices splashing around and ass cheeks almost smack his face. "Ok Josh, I really need to cum RIGHT NOW. Fuck edging." Josh suddenly went completely pale. "You... you're kidding right?"

"No Josh, I'm AAAH - I'll cum right now and it's gonna be amazing, you'll see. Hnnnnngh!"

Josh was in panic - was there anything he could do to prevent this?