Iago

"To spend your life watching over someone...someone with innate ties to you, someone fragile who relies on you...who loves you...that is a feeling I can never forget."  

- Iago, during his breakdown. Koda Sully, referred to exclusively as Iago in Sanguine Melancholia, is a boss and later a party member in the game.

He also appears in Better Days, where he goes by his full name.

In-Game (Sanguine Melancholia)
Iago first appears moments after Carter Alvarez is defeated by the party, introducing himself as a servant of Abilsin. He is quick to engage the party, aiming to destroy them as punishment for meddling in his boss' plans by killing Carter and Bowman. Though the party initially seems to be beyond outmatched due to Iago's incredible power, he eventually starts to cry out in pain, suffering from what would later be revealed to be the chronic pains associated with being a half-demon.

After losing to the Hunters, Iago kidnaps Locke in an act of desperation, hoping to lure them to Abilsin's Throne Room to be destroyed. Despite having abducted him, Iago defends Locke with his life as he escorts the boy to the throne room, succesfully fighting off Vrid when he shows up to kill Locke.

After arriving at the throne room, Abilsin gives Iago the order to kill Locke, which enrages the half-demon. Adrien and the other Hunters arrive in hopes of saving Locke, only to be caught by Abilsin, who promptly gives Iago one last chance to prove his loyalty by killing Adrien. Though Iago quickly prepares to do just that, he hesitates upon seeing just how much Adrien is willing to risk for Locke's sake. He turns on his boss, buying Adrien time to rescue Locke. Upon returning, the party finds that Abilsin is unscathed despite the throne room being in ruins, and Iago is nowhere to be found.

Iago is encountered later on the abandoned train, where he explains that he went there to recover after being beaten by his former boss. Despite parting on decent terms in their last meeting, Iago immediately begins to fight the Hunters once again, still suffering from his chronic pains.

About halfway through the fight, the half-demon breaks down crying and explains that he only ever became villainous in order to drive people away, in hopes of preventing anyone from having to experience grief, which he considers to be the worst type of pain. The loss of his younger sister, Raven, left him in such agonizing emotional pain that Iago decided it would be better if nobody missed him. A pitiful remainder of the battle ensues, and Iago is once again defeated. After the fight, Adrien refuses to finish him off, instead convincing him to join the party.

He successfully escapes Abilsin's cathedral at the end of the game, but vanishes shortly afterwards. His current status is unknown.

In-Game (Better Days)
Koda is first met in the abandoned church in Better Days, where he gives Adrien some information about Carter Alvarez. Later that night, he drags Adrien from his home back out to the church, where he teaches him to protect himself so that he can continue taking care of Locke.

Adrien later finds that Iago had betrayed him and his partner, but upon confronting him, they find that he has attempted suicide. Realizing that he is still breathing, he asks Locke to call for help, and Koda is taken to the hospital where he slips into a coma.

He later wakes up, now having to walk with a cane, as the pills he took had damaged his muscles. He smooths things over with the detectives, and becomes a good friend of both Adrien and Locke.

Voice Lines (Sanguine Melancholia)
Battle start: When attacking: When taking damage: Leveling up: When killed in battle:
 * "I can't promise you a quick death."
 * "Miserable peons..."
 * "This won't take long..."
 * "Would you like to guess whose blood that is?!"
 * [Villainous laughter.] (two variants)
 * “You're hopelessly outmatched!"
 * "Scratchy bitch!"
 * "Naturally"
 * "Are you surprised? I can still grow stronger."
 * "Can you humans keep up?"
 * "Sweet...little...Raven..."
 * "Shed no tears for me..."
 * "At least...the pain is gone..."

Trivia

 * One of Iago's possible voice lines that can play when he takes damage has him calling the opponent a "scratchy bitch." This is a reference to a nearly identical line spoken by the character Baron Brixius from the Sonny series, the main inspiration for Sanguine Melancholia.
 * Iago is the only party member in the main story to have a weapon that cannot be removed.
 * In Better Days, Koda's eyes still have the half-demon effect despite him being human in that universe. It's eventually revealed that he is simply wearing contacts with the pattern, as well as the red colour, though he later swaps them out for blue ones.