Can two adults stay in a hotel?

Of course. An adult can stay in a hotel with a minor. According to Article 24 of the Measures for the Administration of Public Security in Hotel Industry, if the lodging personnel provide their valid identity documents and cooperate with the hotel registration information, they should check their identities with the public security organs and cooperate with the hotel registration information, lead the minors to check in, and go through the check-in procedures after it is reasonable.