The Inflexibility Paradigm.

Penny sighed as she locked her door and slowly made her way down the stairs. It was the middle of the night, the silence eerily soothing to her.

She stopped outside the landlord's room and gently slipped her key under his mat.

Sighing as she straightened up, she headed out of the room, not bothering to look back. She didn't bother to look back at the building as she climbed into her car. She didn't notice a tall, thin man state down at her from his window.

Sheldon Cooper had never been one to express deep emotion after watching someone leave. Even after his father's death, he never shed a tear.

That night, after watching Penny leave, he cried himself to sleep.