Charlie was at the front desk, checking in guests like usual until once of guests got mad that they didn't have any rooms available at the moment

Despite the guests' obvious annoyance, Charlie still spoke kindly to them.

"Sorry, sir, but we're out of rooms," She said, a small smile still remained on her face

That answer didn't make the guests very happy at all. He started raising his voice before raising his hand to hit her. You noticed this and quickly intervened