[It's not leaving behind, its a strategic retreat!]

Sasha...

I know you are a good soldier, but the rules in this world are different. We can't use the things we were taught here. We don't even have our gear.

[And, after all, their opponents are human ones. Who wants to be attacking humans?]

I'll be fine. I've made friends here. I'll try and meet up with them. And the others are out there too. But... I don't want these guys to hurt you. Or take Jean. I think the best way to achieve that is for you to stay hidden. And I want you to have this for now.

[He reaches for his belt, unhooking the first pokeball and holding it out to her.]

It's Amadeus' pokeball. He'll keep you safe.