Despite her already strange body, Jen craved change; as she did when the flu first mutated. Strangely enough though, all this sex was starting to take a toll on her and she felt as if she had to lie down for a bit, perhaps in some cool pristine water. She gave her partner a quick kiss before heading out in search for a large basin of water to fit her.
Kylie didn't take long to start following her mate, she knew Jen was the best fuck in town and she wasn't about to let that walk off on her. As the two walked down the street, Kylie noticed a pack of jocks that had managed to get away from the school. She whinnied in delight and hosed down the group of boys with ropes of her highly corruptive cum. Just being coated in the stuff made them quickly transform. Their cocks grew to the appropriate horse length and became flat headed. Their bodies swelled with strength and they grew taller. Burgeoning breasts grew from their chests and hungry pussies opened up under their monster dicks. Their hair grew out and down their backs, even going all across their bodies, giving them glossy horse tails and fur coats. A few of the horny horse herms stayed to fuck eachother, but the rest ran off to find more "prey".
The rest of the journey was uneventful and soon Jen and Kylie made it to the water supply. Their path had taken them into the forest to the old water supply. Their strong and bestial bodies allowed them to make the journey without difficulty. They knew where the supply was from their past lives, or Jen did at least. It was a place to go with her friends. The water came from a lake, which was pumped up into a cylindrical stone tower after going through a filtering process. The tower had a small entrance at the bottom and a larger one at the top. Knowing that she and Kylie wouldn't be able to fit into the former entrance, Jen began to climb the tower to make it to the one above.
With her tentacles it wasn't very difficult and she swiftly made her way upwards. Kylie followed behind her, climbing with all six of her arms and pressing each of her many tits against the wall while sliding her monster cock between them. As she climbed higher the pleasure grew more fierce until it burst out of her, making her shoot her seed up. The hot load of goo slammed into Jen's pussy, making her shake with pleasure which resulted in a quick shot of cum being fired from her tentacles.
Upon making it to the balcony where the large entrance was, Jen prepared herself for a moment before flinging her eight tentacles at the double locked door in front of her. Her body quivered with pleasure and exertion as she strained to pry open the gate before her. With an excited grunt and no small amount of cum, the metal doors where flung open and Jen took no time in leaping towards her reward. She plunged into the water and a cool chill washed over her, quelling her hot lust for just a moment, before it flared up again. She took down big gulps of the refreshing water. After so much fucking and cumming she had gotten quite thirsty. Her drinking was interrupted, though, when Kylie came hurtling into the pool, displacing a large amount of water with her big body. Jen snorted at her lover, who responded with a quick "giggle", although it came out as more of a soft whinny.
The sight of Kylie reminded Jen of her purpose. The thought of letting her corrupt essence diffuse into the drinking water made her horny and her many cocks began to drizzle cum into the resevoir. Jen approached her mate and wrapped her tentacles around her. Kylie responded in the same way, letting her nipples extend and wrap around Jen. The two rubbed against eachother, Kylie and Jen sandwiching their cocks against their bodies. They went on for hours, cuddling in the water and letting their highly viral fluids out as they went. Whenever they got thirsty they simply drank from the same water they were corrupting to replenish their fluids, effectively replacing the town's water with milk and cum, with the special ingredient of highly contagious horse flu.