She never laughed. He'd liked that when he hired her. He needed someone serious balancing him out. Soon it began bothering him - he wanted to hear it.
He'd tried joking with her. Nary a chuckle. Hijacking a police car scarcely got him a grin.
He should have known the first time she'd laugh would be at him, instead of with.
Gravity was his enemy - unfortunate when testing a hoverboard. Shego cackled as he lay on the ground, while overhead the device zipped around the room.
Pain was secondary to delight. Her laugh was as perfect as the rest of her.