What drove his sudden desire for a nighttime excursion?

"I'll give you ten minutes, then I'll knock on the door if you're not out. If you're worried about waking Bettie up, just sneak out."

"Fine!"

Gritting her teeth, Sabrina retorted icily, "You win!"

She sprang into action, swiftly donning her attire, then stealthily slipped out the door.