The Lost Hero by Rick Riordan

quilts and—Annabeth nudged him. “Snap out of it.”
    Jason blinked. He realized his knees had been starting to buckle.
    “Cabin Fifteen does that to everyone,” Annabeth warned. “If you ask me, this place is even more dangerous than the Ares cabin. At least with Ares, you can learn where the land mines are.”
    “Land mines?”
    She walked up to the nearest snoring kid and shook his shoulder. “Clovis! Wake up!”
    The kid looked like a baby cow. He had a blond tuft of hair on a wedge-shaped head, with thick features and a thick neck. His body was stocky, but he had spindly little arms like he’d never lifted anything heavier than a pillow.
    “Clovis!” Annabeth shook harder, then finally knocked on his forehead about six times.
    “Wh-wh-what?” Clovis complained, sitting up and squinting. He yawned hugely, and both Annabeth and Jason yawned too.
    “Stop that!” Annabeth said. “We need your help.”
    “I was sleeping.”
    “You’re always sleeping.”
    “Good night.”
    Before he could pass out, Annabeth yanked his pillow offthe bed.
    “That’s not fair,” Clovis complained meekly. “Give it back.”
    “First help,” Annabeth said. “Then sleep.”
    Clovis sighed. His breath smelled like warm milk. “Fine. What?”
    Annabeth explained about Jason’s problem. Every once in a while she’d snap her fingers under Clovis’s nose to keep him awake.
    Clovis must have been really excited, because when Annabeth was done, he didn’t pass out. He actually stood and stretched, then blinked at Jason. “So you don’t remember anything, huh?”
    “Just impressions,” Jason said. “Feelings, like …”
    “Yes?” Clovis said.
    “Like I know I shouldn’t be here. At this camp. I’m in danger.”
    “Hmm. Close your eyes.”
    Jason glanced at Annabeth, but she nodded reassuringly.
    Jason was afraid he’d end up snoring in one of the bunks forever, but he closed his eyes. His thoughts became murky, as if he were sinking into a dark lake.
    The next thing he knew, his eyes snapped open. He was sitting in a chair by the fire. Clovis and Annabeth knelt next to him.
    “—serious, all right,” Clovis was saying.
    “What happened?” Jason said. “How long—”
    “Just a few minutes,” Annabeth said. “But it was tense. You almost dissolved.”
    Jason hoped she didn’t mean literally , but her expression was solemn.
    “Usually,” Clovis said, “memories are lost for a good reason. They sink under the surface like dreams, and with a good sleep, I can bring them back. But this …”
    “Lethe?” Annabeth asked.
    “No,” Clovis said. “Not even Lethe.”
    “Lethe?” Jason asked.
    Clovis pointed to the tree branch dripping milky drops above the fireplace. “The River Lethe in the Underworld. It dissolves your memories, wipes your mind clean permanently. That’s the branch of a poplar tree from the Underworld, dipped into the Lethe. It’s the symbol of my father, Hypnos. Lethe is not a place you want to go swimming.”
    Annabeth nodded. “Percy went there once. He told me it was powerful enough to wipe the mind of a Titan.”
    Jason was suddenly glad he hadn’t touched the branch. “But … that’s not my problem?”
    “No,” Clovis agreed. “Your mind wasn’t wiped, and your memories weren’t buried. They’ve been stolen.”
    The fire crackled. Drops of Lethe water plinked into the tin cups on the mantel. One of the other Hypnos campers muttered in his sleep—something about a duck.
    “Stolen,” Jason said. “How?”
    “A god,” Clovis said. “Only a god would have that kind of power.”
    “We know that,” said Jason. “It was Juno. But how did she do it, and why?”
    Clovis scratched his neck. “Juno?”
    “He means Hera,” Annabeth said. “For some reason, Jason likes the Roman names.”
    “Hmm,” Clovis said.
    “What?” Jason asked. “Does that mean something?”
    “Hmm,” Clovis said again, and this time Jason realized he was snoring.
    “Clovis!” he