"If you wanna come for the walk." He gestures out at the cinema carriage. "The mess isn't going anywhere."

Some might say it'd be better for one of them to stay and keep cleaning up, but what does Tidus care about that? It'll get cleaned up either way. Knowing Romeo - and knowing Romeo, he might try and clean up the luggage carriage...!

Which is only a thought that'll come to him once he gets going, with a Romeo in tow. Asking the kid, 'cause why not: "You know who's still on the train in your cabin? Who do you bunk with?"