They had been fighting the latest and greatest supervillain and Tony had been struck with a ray that had been fired when he tried to get an up-close shot of the guy. Now he was sitting in Steve’s lap on the trip back to the tower, hissing at anyone who dare get near them. He had already scratched Clint’s hand when he tried to pet him. He was very demanding, rubbing his head under Steve’s hand and nosing at his elbow. Steve was absently scratching behind Tony’s ears while he thought of what they could do now.
When the Quinjet landed, Steve scooped Tony-the-kitten into his palm and wrapped the other hand around his torso. Tony snuggled into the warmth of his chest and started licking at Steve’s palm, the cat-tongue tickling his rough, calloused skin.
Steve took them in the kitchen and placed Tony on the counter, grabbing a bowl for some canned tuna they had stored in the back of the cupboard. He emptied the can and placed it next to where Tony was lounging and stroked his black fur.
“I’m gonna go ask one of the guys to go out and buy you a litter box, okay? I’ll be right back.” He kissed one of Tony’s fuzzy ears and walked away.
He managed to find Natasha and tell her what to get, before sending her on her way and telling her to leave the items by Tony’s room when she returned. When he got back into the kitchen, the bowl was empty and Tony was resting on the counter and purring. He perked up when he heard Steve enter, struggling to stand up with such a full stomach. Steve lifted him back into his arms, taking pity on Tony after the day that he had had. Tony let out a surprised meow when Steve turned him belly-side-up and kissed his bloated tummy.
“You’re such a cute kitty, Tony.” He whispered. He kissed Tony’s paws as well, making him extend his claws when Steve pulled away. “I love you. I’m sorry I couldn’t prevent this.”
Tony purred, showing he understood, and clawed his way up Steve’s chest. He licked Steve’s cheek and touched his mouth to Steve’s lips. It showed that, though he may be in a kitten’s body, his mind was unaffected and that made Steve relax slightly.
“I’ll fix this, okay? I’m sure it’s just a temporary thing, anyway.” Steve moved Tony back to his chest and lounged on the couch in the living room, turning on the stocks for Tony to watch.
Tony started squirming after about an hour, shuffling his paws and clawing at Steve’s shirt.
“Bathroom?” Steve asked.
Tony perked his head up and stood up. Steve scooped him up and took him over to Tony’s bedroom. The litter box was already set up, sitting in the far corner of the room to provide some privacy.
“You can use the litter box over there, okay? I’ll be right here.” Steve placed Tony in front of the opening in the box and rested on Tony’s bed. The room was rarely used anymore – Steve and Tony had unconsciously decided that they would move into Steve’s room. They had been in a relationship a good two years and had been inseparable because of the threat of their daily lives.
Tony jumped on the bed and snuggled into Steve’s warmth, purring when Steve wrapped his arm around Tony’s tiny form. Steve pulled the covers around them and nuzzled his nose into Tony’s head.
“Good night, Tony. I love you.” Steve mumbled, kissing all of the fur his lips could reach. Tony grunted softly in response, the sound coming out as a squeak with his new voice.
Steve woke up when Tony (sort of) turned back into Tony.
Tony still had his cat ears and tail, but everything else was human. He was still cuddled into Steve and purring happily into his neck, but he was a lot larger and much more comfortable to snuggle with.
Steve kissed the messy dark hair his face was still buried in and breathed in Tony’s scent. He hadn’t smelled like himself as a cat, and even though he had only been a kitten for less than a day, it had still unsettled Steve at the unfamiliarity of it. Steve fell back asleep as Tony nuzzled further in his neck and his soft breaths puffed over Steve’s skin.