Jericho sat up straight again at the next sound, more and more convinced that it wasn't a coincidence. He couldn't see the source, of course, what with that human barrier between them, but he was very certain.

Well, almost very certain. So he tested it one last time:

You ride it!

He waited for the sound. Then:

Do you know which route you want to take? There's different buses riding in different directions, going to different places.

Hearing the sound again, he grinned to himself, strangely excited by the happening. It was weird, wasn't it? But kind of fun. Someone who he only knew from a couple uncertain conversations in text was someone he was within an arm's reach...

One more:

Look to your left. See that map? It has routes in different colors. :)