You're cute when you're worried," she muttered. "Your eyebrows get all scrunched together." "You are not going to die while I owe you a favor," I said. "Why did you take that knife?""You would've done the same for me."It was true. I guess we both knew it. Still, I felt like somebody was poking my heart with a cold metal rod."How did you know?" "Know what?" I looked around to make sure we were alone. Then I leaned in close and whispered: "My Achilles spot. If you hadn't taken that knife, I would've died."She got a faraway look in her eyes. Her breath smelled like grapes, maybe from the nectar. "I don't know, Percy. I just had this feeling you were in danger. Where... where is the spot?"I wasn't supposed to tell anyone. But this was Annabeth. If I couldn't trust her, I couldn't trust anyone. "The small of my back."She lifted her hand. "Where? Here?"She put her hand on my spine, and my skin tingled. I 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. "You saved me." I said. "Thanks." She removed her hand, but I kept holding it. "So you owe me," she said weakly. "What else is new?