@Savannah-and-Bryce0 The instant someone starts inviting others over, without asking permission, is the time you stop that behavior, you don't just let it go on. "I'm sorry, XX, but this is our home- it isn't acceptable to invite other people over. Please respect this, thank you." You send this as an Airbnb message. If he ignores it, or writes back something nasty or threatening, you right away contact Airbnb, refer them to the messages, and ask that they cancel the remainder of his stay with no host penalties. he'll be refunded the nights he didn't stay by Airbnb, automatically.
Give him a 1 star review, (he can't see how many stars you gave him), mark that you wouldn't recommend him, which will prevent him from Instant Booking in the future, and in the written review, just say "XX stayed 2 nights." (or however long he stayed) Other hosts understand what that means.