Peter BlofisProtagonist of the story, son of Sally Jackson and Paul Blofis. Shy and polite in nature, but determined and loyal. Before Percy disappeared, he used to tell stories to the little kid, giving him basic knowledge of the Olympians, Camp Half-Blood, etc. Armed with the basics of what about the demigod world, not really good at handling weapons and defending himself.
- Ascended Fanboy
- Badass Normal
- Brainy Brunette: Though Peter's appearance is not really described in the story, in his official rough character sketch, his hair is brown.
- Deadpan Snarker: He's slowly turning into this.
- Genre Savvy: Is hinted to be this, due to the fact that he has basic knowledge about how Greek Mythology works in the modern world by listening to Percy's storytelling.
- Innocent Blue Eyes
- Muggle Best Friend: To Leon.
- Na´ve Newcomer: Averted.
- The So-Called Coward
- Unfazed Everyman
- Unlikely Hero
Leon HamiltonA son of Demeter, and Peter's best demigod friend. When he was little, he was saved by a demigod and was brought to Camp Half-Blood, and Leon lived the duration of his life there.
- Deadpan Snarker: To Claire.
- Older Than He Looks: He's sixteen when he looks thirteen.
- Messy Hair: Peter describes Leon's hair that it "looked like it wasn't combed for a century."
- The Lancer
- Red Oni, Blue Oni: Leon's Red to Claire's Blue.
- Fire-Forged Friends: With Claire.
Claire WilliamsA daughter of Apollo. Daughter to a former nun (which explains her catholic roots). Has a stoic attitude, although she has a soft side for her celebrity crush Nico di Angelo.
- Action Girl
- Red Oni, Blue Oni: Blue, to Leon's Red.
- Significant Green-Eyed Redhead
- Fangirl: To Nico.
- Fire-Forged Friends: With Leon.
Leo Valdez aka Mr. Flamingo
- Cool Uncle: To the kids of his neighborhood.
- Berserk Button: Whoever "she" is, Leo certainly does not want to talk about her.
- Dark and Troubled Past: Other than his canon backstory, it seems the war a decade ago shaken up fun old Leo.
- Hero of Another Story. Sort of.
- Knight in Sour Armor
- Grease Monkey
- Stepford Smiler -> Stepford Snarker