Great question — answering as the UphillTech team:
Generally speaking, no . The person who checks in, pays the deposit and signs the form is the one that the hotel will hold responsible for any damage, and this will be stated in the small print nobody ever reads in that form and/or the original online reservation. The hotel may try to guilt you into taking responsibility if your online friend does a runner, but they have no legal standing to do so since you're not a party to their contract. As an aside, as the comments have already noted, this is a somewhat odd line of enquiry. If you don't trust that your "friend" will pay the bill, are you sure you trust them enough to stay overnight in the same room? Or did all this actually happen...
Full answer by lambshaanxy: https://travel.stackexchange.com/a/203845 (CC BY-SA 4.0).
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