Thalia Grace
Thalia and Percy quarrel occasionally at camp because their similar personalities tend to clash. Thalia is called "Pinecone Face" by Percy; in retaliation, she calls him "Seaweed Brain", which Percy does not like because it's Annabeth's pet name for him. Thalia goes on the quest to find Artemis, hunt down the dangerous Ophiotaurus Artemis was seeking, and rescue Annabeth, along with Percy, Zoë Nightshade, Bianca di Angelo, and Grover. Thalia, Percy, Zoe, Bianca, and Grover come upon the Junkyard of the Gods and told not to take anything from the junkyard, and just as the group is about to leave, a metal giant rises because Bianca took a figurine of her father, Hades, for Nico. Bianca goes inside of the metal giant and tries to control it, causing the giant to fall over and Bianca to die. Together, they face the Titan General, Atlas's army, and make it to Mount Tamalpais. Already weakened by dragon poison, while facing her father, Atlas, Zoe dies from a final blow from Atlas. There, Thalia fights her old friend Luke, and it seems that she has strong feelings for him, and they discover that Kronos used Thalia to twist destiny into her hands, since she would be turning sixteen on the day following the Winter Solstice. She escaped this deadly path and turned to her half-sister, Artemis, who made her a Hunter, which would stop her from being sixteen, because whoever becomes a Hunter becomes immortal, unless they shall die in battle, or break the oath by falling in love.