Clarisse La Rue is a Greek demigod, a daughter of Ares, the Greek god of war. She was the former head counselor of Ares' Cabin, before stepping down and giving the role to Sherman Yang. She is currently attending the University of Arizona and is the girlfriend of Chris Rodriguez. 

Clarisse is mentioned when one camper comments on how Jason Grace's weapon is better than Clarisse's spear, Maimer. She is again mentioned when Leo reveals Festus to the camp brandishing her spear stating they should kill Festus. She takes part in a council meeting once Jason regains his memories. Chiron reveals the truth about the Roman camp. She mentions that the brutal philosophy of the Romans makes sense to her, as Ares is the god of war so his children like violence. However, she does not like the concept of Greek demigods working/cooperating with Roman demigods, as they were enemies before.