Originally Posted by
serfty
It means one guest staying in the same room. i.e. a room booked for 2.
I don't agree with this interpretation. The text reads:
You will receive complimentary Continental breakfast for you and up to one additional registered hotel guest each day of your stay.
I think the language is rather specific. If there was a requirement that the other guest be registered in the same room, and not just in the hotel, they would have said so.