" Oh, was that liquor of yours a stimulant?" asked Elena. "I wondered why he didn't fall asleep."
"Couldn't you tell?" chuckled Mayhew.
"Not really."
Miles twisted his head to take in Elena's upside-down worried face, and smile in weak reassurance. Sparkly black and purple whirlpools clouded his vision. Mayhew's laughter faded. "My God," he said hollowly, "you mean he's like that all the time? "

― Lois McMaster Bujold , The Warrior's Apprentice (Vorkosigan Saga, #2)