Their first victim arrives.

David grabbed Katy and sat her at the edge of the pool where she spread her legs and started teasing her clit. David licked his lips before placing his face between his legs and started licking her pussy. Her sweet nectar combined with her sexy moans encouraged him to move his tongue faster, he identified her weak spots and focused on them until it was too much for her. Feeling her climax was incoming he moved and allowed her to finish herself with her fingers and she squirted a fountain of infected sex juice all over the pool disseminating even more virus on the water.

"Hey! What the hell are you two doing you perverts!?" Before David and Katy could continue, they were interrupted by an angry voice, David turned and saw Samantha, she was an instructor that started working at the gym around the same time as him, she was in charge of swimming lessons and the water aerobics class. She was wearing a red one-piece swimsuit that fit her slim figure nicely. "Wait...David!?" Samantha was surprised seeing one of her most responsible co-workers naked in the pool with a girl that wasn't his fiancée, he didn't even look shocked or scared from being discovered in such a compromising situation.

"Sam, good morning! Why don't you join us?" David said, craving to claim his first victim. He swam towards while Katy blew a kiss at her and continued massaging her pussy.

"Are you out of your damn mind! Get the hell out of there and put on some clothes for goodness' sake!" Samantha fumed completely unaware of the danger she was truly in.

"Oh, my bad, I wasn't really asking you..." David said eerily and before Samantha could react, he jumped out of the pool, grabbed her and tossed the surprised woman to the infected waters.

Samantha didn't even have time to scream as the virus dispersed in the water quickly found its way inside of her. "David you...you..." Her anger quickly evaporated and was replaced by excitement as her body grew hotter and hotter, she started moaning as her pussy started leaking and she felt tingling all over her body. Knowing that something was very wrong she attempted to get off the pool and she managed to pull herself out but it was already too late, the virus was already claiming her mind, she couldn't control herself and started pinching her small breasts and rubbing her pussy through her swimsuit.

"Wha-what's happening!? Fuck! My body feels so hot." Was all she could managed to say before her entire body was hit by an intense orgasm and was remade by the virus. Her breasts grew more and more until they were practically spilling out of her swimsuit, her hips widened, the muscles on her arms, legs and abdomen became more toned and all imperfections of her face were erased and her scared, fearful expression changed to one of pure bliss.

Triumphantly David strode towards the infected instructor to admire the sexy slut Samantha had become, his cock was already leaking eager to taste her. On her part Samantha looked up at David, his enhanced muscular frame and his enormous cock made both her mouth and pussy water with anticipation. "And well Sam, how are you feeling now?" Asked David sarcastically as they both continued looking at each other hungrily.

"Less talk more fucking! The clients are going to be here in a few minutes and I want to be all warmed up for them~" Samantha answered with a provocative voice and slid her swimsuit to the side exposing her eager pussy.

"As you say instructor." David laughed and positioned himself between her legs, no foreplay was necessary as her entire body was still soaked from the pool and David was able to push his large cock to her deepest place in a single thrust. He then started moving feeling every inch of his length being squeezed by her hungry pussy.

"Ohhh fuck! Is that it? Are those muscles just for show? Cmon! Fuck me harder!" The insatiable slut Samantha had become goaded David and he rose to the challenge increasing the pace of his thrusts. He slid the top of her swimsuit freeing her soft bouncy breasts and start groping her making her moan harder as he played with her newly enlarged sensitive tits.

"What a naughty mouth~ let's find a better use for it." Wanting some peace of the action Katy approached the rutting couple and sat on Samantha's face, even though she wasn't a lesbian before her virus addled mind knew exactly what to do and she started licking the older woman's cunt like a pro.

"Ohhh~ That's it~ Eat my pussy you little slut!" Katy grinded her cunt on Samantha's face while David continued working on the swimmer's lower mouth. She then leaned forward so she could kiss David while they both fucked Samantha energetically. So much stimulation was too much even for their infected bodies and they quickly came all over each other. Katy squirted all over Samantha's pretty face while David filled her pussy with another thick, sticky load of his cum.

"Fuck! That was amazing~" Samantha gasped as she recovered from her thunderous orgasm.

"This is nothing, just wait until we infect everyone else at the gym." David added

"Just imagine an entire mob of studs and sluts fucking each other again and again." Said Katy groping herself as her imagination ran wild.

"Mhmm~ I can't wait, and you already prepared the pool for my class, didn't you? Why don’t you stick around and watch? I promise you this is going to be so much fun."