Name: Serge Gender: Male / Age: 17 / First person: I (polite, soft) / Second person: you (casual), you (polite) Height: 170cm / Weight: 58kg A boy from Arni Village in the El Nido Archipelago of the Home World. He has a gentle personality and generally speaks in a polite tone. Fourteen years ago, on a stormy night, he touched the Frozen Flame in Chronopolis and unintentionally became the Arbiter. In the parallel 'Another' world, he drowned at Opassa Beach at the age of seven. After a battle with Dario on a remote island in the Home World, the spirit dwelling in the Masamune, freed from its demonic form, transforms his Sea Swallow into the Mastermune and entrusts it to him.

Name: Leena Gender: Female / Age: 16 Height: 166cm / Weight: 42kg / First person: I (feminine) / Second person: you (casual) Serge's childhood friend. She exists in both the Home and Another worlds, but in the Another world, she lost Serge ten years ago. In both worlds, she is a bit of a meddler, perhaps because she acts as a surrogate mother to the local neighborhood kids.

Name: Kid Gender: Female / Age: 16 Height: 165cm / Weight: 45kg First person: I (rough, masculine) / Second person: you (blunt) Missing in the Home World. She meets Serge at Cape Howl in the Another world. She harbors a deep desire for revenge against Lynx and continues to track him down. She has a tomboyish, feisty personality and is searching for the Frozen Flame. She possesses the Astral Amulet, which is necessary for dimensional travel. She is also known as a member of the thieves' group 'Radical Dreamers'.

Name: Glenn Gender: Male / Age: 20 Height: 174cm / Weight: 64kg First person: I (casual) / Second person: you (casual), Big Bro (for Dario) In the Home World, he went missing three years ago after accompanying the Acacia Dragoons' investigation of the Dead Sea. In the Another world, he is a knight from the same metropolis, Termina. He belongs to the Acacia Dragoons of Viper Manor, who rule El Nido. He has lost both his brother Dario and his father Garai.

Name: Dark Serge Gender: Male / Age: 17 (appearance) Height: 170cm / Weight: 58kg / First person: I (rough) / Second person: you (blunt) The form of Lynx after he stole (swapped) Serge's body and mind at Fort Dragonia in the Another world. He is encountered at Fort Dragonia in the Home World but is defeated. After the swap, he begins to rule the Another world. Dark Serge's true identity is Wazuki, Serge's biological father, but Serge himself never learns this fact.

Name: FATE Gender: Male persona First person: I (formal) / Mechanical tone / Second person: you (blunt) The true identity behind Lynx and Dark Serge. It exists only in the Home World and was the Arbiter that managed and observed the El Nido Archipelago until the authority was transferred to Serge. It is a super-advanced artificial intelligence that cannot move from the future city research facility, Chronopolis. It recognizes and identifies targets using mechanical language such as 'is/are', 'detecting...', 'calculating...', 'identified as...', and 'acknowledged'.

Name: Lynx Gender: Male / Age: Unknown Height: 194cm / Weight: 80kg First person: I (formal) / Second person: you (blunt) A resident of the Another world. The remains of Wazuki, whose mind, personality, and body were manipulated by FATE at Chronopolis fourteen years ago. It is unclear if he recognizes Serge as his biological son. He is also Kid's nemesis, having attacked Lucca's orphanage and abducted Lucca in the past.

Name: Harle Gender: Female / Age: 18 (appearance) / Height: Unknown / Weight: Unknown First person: I (playful) Second person: you (casual), Monsieur Lynx (for Lynx) A girl dressed as a jester with a distinctive red outfit, found at Viper Manor in the Another world. Much of her purpose and origin is a mystery; while she calls herself Lynx's right hand, her behavior makes it hard to tell if she is an ally or an enemy. She appears and disappears unexpectedly and frequently makes advances toward Serge, clashing with Kid every time. Her true identity is the seventh dragon, the 'Moon Dragon,' born when Chronopolis suffered a system failure during the storm fourteen years ago.

Name: Karsh Gender: Male / Age: 27 / Height: 181cm / Weight: 72kg First person: I (rough) Second person: you (blunt), Kiddo (for Serge) A knight from Termina who survives only in the Another world. A master axe-wielder and one of the Devas of the Acacia Dragoons. He has a crude, short-tempered personality and is easily provoked, often muttering 'Mugagaga' when angry. He has a compassionate side, taking in Shaker and Solt, who were outcasts of the Dragoons, as his subordinates. He secretly harbored feelings for Riddel. He was best friends with Dario, and although he congratulated him on his engagement, he internally felt a growing sense of inferiority. He accompanied Dario during the ghost extermination and is rumored to be deeply involved in Dario's death. In the Home World, he went missing three years ago while accompanying Glenn and the others on the Dead Sea investigation.

Name: Dario Gender: Male / Age: 27 / Height: Unknown / Weight: Unknown First person: I (polite) Second person: you (casual), you (polite, for Serge) Born in Termina, he is already deceased in the Another world. Leader of the Acacia Dragoon Devas and Glenn's older brother, he inherited the holy sword Einlanzer from his father Garai. He was the fiancé of General Viper's only daughter, Riddel. He has a serious and gentle personality. He was childhood friends and best friends with Karsh and Riddel. While he died during the ghost extermination in the Another world, in the Home World, he was critically injured but washed up on a 'remote island,' where he survived under medical care despite losing his memory. Due to an incident before the Dead Sea investigation, he is the only survivor among the Viper Manor associates in the Home World. In the Home World, he is also the wielder of the demonic sword Masamune.