[Armin suspects that the fights, should there be any (and there likely will be), will be more than a simple "brawl," as Kaito puts it; that being said, he's not about to give away what little weaponry he has (it's all attached to his body anyway).

[He does, however, quietly draw one of his blades, turning it up flat to show Kaito.]

I'll cut through the vegetation with this. Let's move as quietly as we can and see what's on the other side. [Of course, Armin's real goal is getting this person safely through the forest to whatever lies beyond, but he won't potentially insult Kaito's pride by saying so.]

If you see an enemy, it's possible that they'll be willing to negotiate, but not guaranteed. Our best bet is to run, and only fight if we need to. [With this, he gives a firm nod.] If I can count on you to watch my back, then you can count on me. What do you say?