They're either attending Chaor's Underworld Victory Celebration or Lord Zedd's Annual Monster Mash. Either way, Hinami, you could've told Tsukino a bit sooner. For a "Divine" Being, you are incredibly slow when dispensing Nah-Lidge.
"We're an anomaly, not a novelty.
Enter at your own risk, private property.
Do not trespass, beware of dogs.
Bear traps, alarms, and a right to bare arms.
Where laws ain't applied, my jaw's homicide.
The water ain't safe, whoever said it was lied!"