|“||Apollo had said he knew what this kind of love was capable of. And I finally understood why Paris had risked his country and his blood for Helen. Selfish, yes, but I understood. I would burn the world if that meant Alex would be safe.||”|
– Aiden St. Delphi, Elixir
Early life: He is born on October 30th. On the night of his parents' deaths, a half-blood sentinel risked his life to protect both Aiden and his brother, Deacon St. Delphi. The half-blood's sacrifice led Aiden to believe that he had a duty to protect innocent half-bloods and pure bloods. Instead of taking his family's seat on the council as expected, he became a sentinel. Years before the novel Half-Blood, Aiden caught sight of Alex in the training room sparring with Caleb. This is mentioned in Elixir. Her laughter and easy nature piqued his attention. She was sixteen, while he was eighteen back then. At the beginning of Half-Blood, he is twenty.
Aiden has wavy, dark brown hair that always falls in his face, and quicksilver grey eyes. He is believed to be around 6'5". Alex mentions numerous times that he is very attractive.
Alexandria 'Alex' Andros: Alex and Aiden have a complicated relationship. Aiden first noticed Alex when he was eighteen and she was sixteen. He noticed her laughter and easy nature back then. In Half-Blood, he agrees to train her so that she can graduate her training on time. They constantly have disagreements at first, with Alex thinking Aiden doesn't know how to fun and Aiden thinking Alex is too reckless. Although the sexual tension between them is strong, they refuse to start a relationship since it is forbidden. They become closer in Pure, but their romantic relationship starts in Deity. There is also conflict because of Aiden being jealous of the Apollyon connection Alex has with Seth. He and Alex later become a demigod after a deal Seth made, which allows them to be together forever.
Deacon St. Delphi: Deacon is Aiden's younger brother. Aiden takes care of him after their parents were killed at a young age. Aiden cares for him very much and hates it when Deacon drinks and goes out partying.
Luke Ritter: Aiden thinks that Luke and Deacon are good together, despite the fact that Luke is a half-blood. This is also because Aiden has fallen for someone that is not a pure like him as well. Aiden is supportive of Deacon's relationship with Luke, finding Luke to be a good influence to Deacon.
Seth Diodoros: Seth and Aiden are rivals for Alex's affection, but eventually they become somewhat mutual friends after Seth sacrificed his freedom to have Aiden be able to be with Alex for eternity. Aiden's anger towards him also alleviates after Seth begins to fall for Josie.
Josephine 'Josie' Bethel: When Aiden meets her in The Power, he seems to respect Josie and thinks that she is good for Seth. Aiden sees Seth's child in the fourth book, The Prophecy. Aiden wishes that he and Alex will have their own child someday. He also tells her he trusts Seth to be a good father to Leon.
Aiden is strong-minded and brave. He is caring, romantic, proper, a rule follower, and great in combat. After feeling the need to protect half-bloods and pures, he turned down his family's chair in the council and instead became a Sentinel. His brother Deacon says that he grew up too fast and is too uptight for his own good.
"Then I should be relieved to know what I was told an hour ago is false. It wasn't you who yanked a girl-by her hair-out of a chair in the common lounge area."
"Agapi mou." (Means "My love" in Greek) --Aiden's nickname for Alex that he begins to call her since Half-Blood
"You are my everything."
"My heart stopped when that damn door closed on me. I could hear you two fighting. I could hear him taunting you and I could hear him breaking your bones. And there wasn't a damn thing that I could do about it."
"And because I love you, I am willing to die to save you from that. Don't you dare take that decision away from me again."
"Zoi mou." (Means "My life" in Greek)
"We need to get him a bell." --Aiden about Apollo barging in at the worst timing whenever he and Alex are hooking up
"Because I love you, we share each others problems."