“The more I did it―the more it owned me. It made things matter. It put a spine into my spineless life and that spine spread, into backbone, ribs, collarbone, neck held high.
It was something. Don't say it wasn't.”

“Having a spine is overrated. If everybody squealed and ran away, there'd be no more wars.”

“She (Annabeth) put her hand on my spine, and my skin tingled. I (Percy) moved her fingers to the one spot that grounded me to my mortal life. A thousand volts of electricity seemed to arc through my body.”

“The best lightning rod for your protection is your own spine.”

“Along crags and sunless cracks I go,
Up rib of rock, down spine of stone,
I dare not slumber where the right winds whistle,
Lest her creeping-soul clutch this heart of thistle.”

“I missed him. Love, I realized, was something your spine memorized. There was nothing you could do about that.”

“You lack the requisite spine and testicular fortitude to study under me.”

“Resisting the slow touch of a frozen finger tracing out my spine.”

“I couldn't stand the pain. All the doctors said there was nothing wrong with my spine because there was nothing they could see. But the chiropractors said they thought they could help and they did.”

“It takes a lot of spine and stomach to make yourself into something when no one gives you a foundation.”