Hi, I'm Swiftwind

Swiftwind skids to a stop on the other side of the portal. She glances around as the cool of the night surrounds her. She purrs loudly. "Wait," she meows, "I'm still a cat." She tries to morph into a human, but fails. "Mouse-dung!" she hisses. "Now what do I do?" She pads toward a dark, looming building. It isn't marked, but Swiftwind can tell by scent and aura that it's her target. She stalks her way to the edge of the barbed wire fencing. No gate is visible, so she begins digging. "This would be so much easier for Rabbitleap." she growls. Finally, she manages to dig a hole deep enough to squeeze herself through. Almost immediatly, an alarm goes off. "Oh fox-dung!" A bright light flashes onto her from a guard tower as she sprints to the large double doors of the building. A dozen guards rush out, looking around wildly for the intruder. They relax and put down their weapons. One pulls out a cell phone.
"False alarm. It's just a cat." he relays.
"Oh dear, um, when in doubt, act adorable." she whispers to herself. She drops her ears and widened her eyes, giving the sweetest face she can. A tall, muscular young man breaks through the crowd of guards and examines Swiftwind. 
"Aren't you cute?" he observes. He checks Swiftwind over. "And you don't have a collar either." He turns to a man in a black suit. "I think it's a stray, can I keep it?" The man just looks at him.
"Are you serious?" he asks. "You're a grown man, and you want a little pussy cat to hang around with?" The two men look each other in the eye for a few moments.
"Yes." states the young man. The other guy surrendurs.
"Alright. As long as it doesn't have rabies." The man walks away with the guards, leaving Swiftwind and the man who she thinks is Captain America alone in the courtyard. He picks her up and holds her for a bit. 
"I'm gonna call you... Ranger." he decides.
"I'm a girl! My name is Swiftwind!" she yells, but to him it just sounds like a mew. He brings her inside the building. She glances at the digital clocks on the wall. "Wow. It's like, nearly midnight. At least I found you Captain. First part of my mission, completed successfully." The Captain looks at her.
"You're a talkative one, aren't you, Ranger?" he asks. He takes her down several hallways to a door marked INFIRMARY. She sees needles and leaps out of his arms, running the other way. 
"Vet! Oh no, you are not taking me to the vet! I have rights as a human being! Even though I might not be one at this very moment. You are not fixing me!" she hisses. He just stares at her in shock. 
"Wow. You really don't want to go in there. Fine." he sighs, "I'll take you in the morning." He picks her up again, this time taking her to his quarters. He tosses a spare blanket onto the floor in a corner of his room. Swiftwind paws at it and circles a few times before lying down and watching Captain America intently. She silently waits as he goes to bed and falls asleep. She gets back up.
"Okay, now I can morph." She throws her head back and stands up on two legs. She examines herself, realizing she's human once more. "Cool. That would have been so much more helpful earlier." She touches the rolled up jeans and tank top that she wore when she morphed into a cat. "At least I have clothes this time. So glad TrailBlaiser worked out that bug with my powers a while back or this would have been awkward." she whispers. She looks over at him, sleeping soundly. Now what?, she thinks. An idea strikes her. She morphs back into a cat and jumps on his stomach, startling him. She jumps back onto the floor as he stares at her in disbelief. 
"What?!" he growls. She morphs into a human.
"Hi, I'm Swiftwind."