[Okay, this isn't going as well as he'd hoped. Riku pauses to take a few deep breaths, shutting his eyes and rubbing his brow. How to put this...?]

Okay, so... first thing you oughta know is that this world likes to bend the rules a little. People drop in from different points in time, and I'd say Sora's from pretty far into the future.

[...]

...I know that doesn't make a lot of sense, but trust me. You'll be fine.

[Though it's troubling to think of what could've-- probably happened to her, so there might be a slight uneasy edge in his words.]