@Ian27826 There's no need whatsoever to feel embarrassed about mentioning it to her just because she responded politely and responsibly. Many guests, especially those new to the platform, make assumptions about what is and isn't allowed at a Airbnb and as long as a host isn't aggressive about cluing them in, it's important knowledge for them to have.
One of my very first guests, a young gal, first Airbnb booking, booked for one (which is all I host in my private room) and arrived alone. She went into town that night, I went to bed, and in the late morning, when I was having coffee, she emerged from her room with a guy. As a newbie host, who never had read any hosting forums, I was quite shocked, assuming it was someone she'd picked up from the bar (she wasn't from around here). She right away, quite innocently, introduced me to "My friend XX" and after I greeted him, said to her, gently, "You booked for one person and I only host solo travelers." They both looked so shocked and crestfallen that I could immediately tell she wasn't trying to pull a fast one and asked whether they really wanted to squish into the single bed for a week, to which they replied no problem, they were quite cozy. So I charged them a little more, and let him stay, and they were very sweet people. (Turned out they hadn't see each other for 6 months, were "sort of" boyfriend/girlfriend who had a tentative plan to meet up in my town, and were thrilled to be together again).
But I told her that even though I wasn't going to mention it in the review, she should be aware to always book for the correct number of people, and if not sure, convey to the host that there may be someone joining her, because she could get a really bad review for that in the future.
