In fact, most hotels are like this.
As long as you check into the hotel alone and successfully obtain the room card, you can return after a few minutes, whether alone or with someone else. In hotels where you can enter without a card, you can let your companion go directly to the room after a couple of minutes. In 99% of cases, no one will pay attention to you.
If you insist on checking in together at the front desk, the front desk staff might require everyone to present their ID cards, which has a relatively high probability (but it's not 100%).
I actually saw two people check in together once, a man and a woman, and the woman didn't have her ID. She got into an argument with the front desk, possibly because she was in a sensitive profession or maybe she really forgot it. I was silently complaining to myself, thinking, why did they have to go to the front desk together when one of them couldn't provide an ID? It was clearly making things difficult for the staff.
That day, at the same hotel, after I checked in alone, my female online friend came over (no registration required, and no one cared). We stayed together for two days and nights, and during that time, we went in and out separately or together many times, and no one paid attention. We sneaked a glance at the front desk when we entered and exited, and the staff didn't even look at us.
This type of management system is actually very similar to the epidemic prevention policies during the pandemic. For example, during the pandemic, you were required to wear a mask, but no one checked if your mask met medical standards. You could wear a medical mask for a year until it turned black, but if you wore an N95 or gas mask every day for 100 days and then went out without a mask on the 101st day, that would not be acceptable. As long as you cooperate with the hotel staff on the surface, they really don’t care about the actual situation. But if you openly refuse to cooperate, they have to enforce the rules due to their work processes.
