Reverse Isakai, looking for a guardian/partner for an assertive loli. (MxF)

So... Here's a funny idea I had for a few days. I like Isekais. That "fish out of water" scenario might be a bit repetitive, but it is interesting how characters develop when taken out of their usual environment. And while doing the usual formula in reverse isn't anything new, I still would like to take a shot at it. So? In a current day setting, imagine this scene:

It's late at night. Your character just finished their shift and is on his way home. After getting off the train, and out of the station, the shortest route to his apartment is through a park where a handful of urban myths are supposed to have happened. Not that your character can confirm any of that. Probably has played there when he was a kid. But on this night, something does happen. With a deep whirl, a portal opens somewhat near to him, and through it falls something. A demonic, winged creature with purple skin and muscular body. His back towards the ground, with two large spikes protruding from his body. Or so it seemed. It were swords, because at his front, was a girl who was still pushing her swords down into him.
The portal closed, and the demon let out a laugh. "Ti tut... umrosch." And begins turning into what can best be described as charcoal. Just black at first, then brittle, and finally into dust.
But the girl? Now that the bigger creature was not blocking the view, it seemed as if she was bruised, and had cuts along her sides. Exhausted as well, judging by her heavy breathing.
When your character moved (whenever to approach or to get away is up to you), she'd raise one sword at him, yelling "Stoi!" But upon looking at him, seeing his condition, and probably no weapon, she'd lower her sword.

And that's the premise I would like to start with. A young looking girl in a new world, where she does not understand the local language. But she would understand people, concepts such as money, crime and punishment. She'd also try to learn this new language if she had some books (probably children books since they are quite beginner friendly) and a bit of help. I feel like there is potential for a sweet story here, so... anyone interested? And because I know I like eyecandy, and so might you, here is the character I would like to use.

Personality wise, you can expect a lovely, smart little girl, with a mature understanding of the world around her, and a clear interest in someone who helps her through these trying times. She will also come with some magic abilities, as well as some financial strength, but nothing that would be too useful to her if she was completely on her own.

Also, while I would prefer to do this with the setup that she doesn't speak english, I can adjust that I guess. I just really like the idea of her communicating simple things with gestures, and slowly get into speaking simple phrases, and eventually learn enough to talk. Growth, you know? But yeah. I get that it's not everyone's cup of tea, so we can drop that if you like.

If there are any questions left, by all means, ask away. Hope to hear from you soon.