Everything has already been taken care of for Travis. He had permission from both his parents and Sarah's and the paperwork has been filled out for his second dose. All that was left was for Sarah to 'administrate' the second dose.
However, Sarah wasn't just gonna give Travis a drink of milk and be done with it. Travis's change will inevitably lead to sex and she wanted her first time to be special. Travis's mom had already given her pills to keep her from having pups so she and Travis didn't have to worry about that.
The two of them were currently up in Travis's bedroom, kissing each other. However, Sarah was still keep her lips closed so that her saliva wouldn't affect Travis too soon. It was still incredible enough to her that she'd be kissing a boy in her underwear. Travis was still wearing his, too, but that still made her a little nervous. Eventually, Sarah pulled away from Travis and said, "I think it's time." With that, she reached around and undid the clasps to her bra. Her large breasts soon bounce free, her arousal making her nipples very easy to see within her fur.
"Ok then," said Travis, reaching out to her breasts.
Sarah covered her nipples and said, "No, Travis, not quite yet."
Travis gave her a puzzled look and said, "Well if you're not gonna let me taste your saliva or your milk, how are you supposed to give me a second dose?"
"Any of my bodily fluids would work, including..." said Sarah before pulling down her panties. Her vagina was a little hard to discern at times with her fur, but Travis could see her wetness and small her arousal.
"Wouldn't you rather wait until I'm bigger?" asked Travis. While he didn't like admitting, Sarah towering over him was a bit intimidating for him. He wasn't puny himself. He was actually in pretty good shape for about a 14-year old, but he constantly felt overshadowed by the double-dosed members of both his and Sarah's families.
"Travis, I want my first time, OUR first time, to be special and unforgettable," said Sarah before leaning and whispering huskily, "That's why I want to feel you growing inside of me."
That immediately sold Travis in on this. He stood up and pulled down his briefs. His canine dick soon sprang out. It was a healthy size, being at least five inches, but Travis was a little embarrassed if Sarah thought it was small. However, Sarah only smiled and pushed Travis gently down until he was sitting on the edge of his bed. She reached down and rubbed his bright red shaft. The young Dalmatian gave a soft moan at that. Sarah slowly lowered herself until his head was pressing against her lips. Taking his cue, Travis slowly pushed up and into her. Sarah let out several gasps at that before he fully hilted. To be honest, Travis still felt a little small to Sarah, but he was more than long enough to break her hymen. But once she recovered from that, she started to move up and down, discomforting changing into pleasure.
Travis's changes soon became apparent. He slowly started to increase in size. His arms and legs increased in length while becoming thicker with muscle. His torso started to expand and grow. His lightly-defined muscles became a lot more obvious as they hardened into pecs and abs of steel. He grunted as he pushed deeper into Sarah. "You're so tight..." he moaned, his voice already sounding deeper.
Sarah moaned as she felt his dick start to grow inside of her. What had been modest before was quickly filling her up. She could swear she could feel his balls also swelling as they bumped against her. "Oh, Travis, you feel so good..." she moaned as she pressed her hands against his chest. running her fingers through his spotted fur and feeling the hardening muscles building up. Travis's thickening dick urged Sarah to start bouncing more, which naturally made her breasts start bouncing. Travis reaching up and cupped them, his large hands making her globes less of a handful. He licked her right nipples before he started sucking on it, tasting sweet milk. Sarah only moaned louder as she bounced even more, Travis thrusting to keep up with her.
Soon, Sarah felt her core start to tighten. "Oh, Travis, I'm so close, so close, please don't stop," she said breathlessly.
"You got it," growled Travis, his voice a deep tenor. He thrust deeper into the Husky, feeling her tighten even more around his shaft. It came as quite a surprise when both of them felt the base of his dick expand and push deep into her pussy. But they only had two seconds to think of that before they both let out a howl of orgasm. Sarah's pussy clenched hard as Travis shot his load into her. The two dogs felt back on the bed and panted, their bodies slowly cooling down.
Sarah took the time to see how the mature Travis looked. The second dose of the Animalia virus had given the body of a champion. Well, maybe he wasn't as overly-muscled as Samson, but he definitely look he could be a middleweight bodybuilder. His white fur made no secret of his impressive muscular definition and his black spots kind of made him even more appealing. His face didn't really change much asides from getting a little bigger. He actually resembled his father quite a bit, except that his snout was a bit slimmer and he had a different spot pattern.
"So, was I good for your first time?" asked Travis, his voice deeper and more mature.
"The best I could have ever expected," said Sarah, "Though I bet we were a bit noisy. Your parents probably heard the whole thing."
Travis chuckled and said, "If they were even paying attention. What do you think they've been doing this whole time?"
Sarah paused and listened, her sharper hearing picking up the sound of squeaking bed springs not too far away. "Worried about getting brothers or sisters?" she asked.
"That won't be happening for a while," said Travis, "Besides, you're all I want to have right now."
Sarah smiled and nuzzled Travis's nose. "I love you," she said softly.
"I love you too," said Travis before he kissed her. This time, Sarah didn't hold back. While their muzzles weren't quite the right shape for very deep kissing, they were still making the most of it. Sarah never imagined she'd loose her virginity like this, as a Husky woman mating with a Dalmatian man. But she couldn't argue that she loved every moment of it.