Luna

“Nico drank from the chalice, then offered it to Jason. "You asked me about trust, and taking a risk? Well, here you go, son of Jupiter. How much do you trust me?"

Frank wasn't sure what Nico was talking about, but Jason didn't hesitate. He took the cup and drank.”
― Rick Riordan, The House of Hades

“Even the gods couldn't devise a fates so twisted.”
― Rick Riordan, The House of Hades

“Is this guy Love or Death?" Jason growled.

Ask your friends, Cupid said. Frank, Hazel, and Percy met my counterpart, Thanatos. We are not so different. Except Death is sometimes kinder.”
― Rick Riordan, The House of Hades

“About five meters ahead, Nico was swinging his black sword with one hand, holding the scepter of Diocletian aloft with the other. He kept shouting orders at the legionnaires, but they paid him no attention.

Of course not, Frank thought. He's Greek.

[...]

Jason's face was already beaded with sweat. He kept shouting in Latin: "Form ranks!" But the dead legionnaires wouldn't listen to him, either.

[...]

"Make way!" Frank shouted. To his surprise, the dead legionnaires parted for him. The closest ones turned and stared at him with blank eyes, as if waiting for further orders.

"Oh, great..." Frank mumbled.”
― Rick Riordan, The House of Hades