They won't stick out at all. If I remember correctly, our hosts brought along some of their own pokémon as well. As for dos and don'ts...

[France pauses briefly, a short flash of surprise passing over his face.]

I can't really think of any don'ts besides making sure they don't get into too much trouble. I suppose it would be a bit much to bring some of the larger pokemon inside. I wouldn't suggest bringing a Wailord.

[There's a light, jesting note to his tone on the last sentence.]