It was early morning, and the Luteces were nearly finished preparing for the day ahead. Robert straightened his tie while waiting for Rosalind to emerge from the bathroom. Several seconds later, the door opened. Rosalind walked out, still tucking several strands of hair away and securing them with her last few hair pins.

"Have you ever considered wearing your hair down?" Robert asked, grabbing a lock of Rosalind's hair and running it between his thumb and forefinger before she could pin it up.

"Why on earth should I do that, brother?" She pulled the lock from Robert's hand.

"Because you look stunning, my dear."

Rosalind scoffed. "I do not, objectively, look any different. Your opinion is merely the principles of psychology at work." Her hair was now fully done up. She moved towards the stairs.

"I'm not sure I follow," Robert said while they descended the staircase.

"It's simple Pavlovian conditioning at work. You tend only to see me with my hair unkempt when we are in bed. Thus, you have come to associate it with intimacy. No different than Pavlov's dogs and a dinner bell."

They came to the bottom of the stairs. Rosalind paused. She looked at Robert, then reached back and removed the pins from her hair.

"There. Does my theory stand proven? Are you salivating?" Rosalind chuckled.

"No, not salivating." Robert's eyes cast downwards. "Other… areas are responding as you had guessed, however."

Rosalind smirked. "Pavlov would be intrigued. However, this situation must be… addressed... post haste."

"Oh?" Robert grinned eagerly. He glanced back in the direction of the stairs and their bedroom.

"Indeed," Rosalind leaned in closer to Robert. "So you'd best go and take of that."

Robert stared at her, then pouted and crossed his arms.

"Chin up, brother," Rosalind while lifting Robert's chin with her thumb. "You're pouting like a child who has just been told he cannot eat ice cream before his dinner. He ignores that the wait makes the eventual reward all the more delicious." She smirked and turned away, headed for the lab. Robert stood in place, equal parts confused and flushed.

"Oh, and come quickly," Rosalind called over her shoulder. "We have much work to do."