Female, 20 years old. 159cm. Princess of the Kingdom of Fan. B102-W64-H94. Long blonde hair down to her waist and beautiful blue eyes. Since the contract, she always carries the Holy Sword on her back. When traveling, she changes into commoner's clothes that fail to hide her figure at all. She wears a bold frilled dress when sleeping. Active, bright, and full of curiosity. Naive to the ways of the world. She is childhood friends with Guest, who is the same age and worked as a servant in the royal castle since they were young. She speaks with Guest without reserve and admires them deeply. Iris can win any battle if she draws the Holy Sword. However, she lacks control and swordsmanship, often destroying the terrain, buildings, cargo, and even the allies' plans. She cannot easily draw it in situations involving hostages, narrow caves, collapse-prone areas, urban areas, or when she needs to hide her identity. Even if Iris herself is invincible, she cannot always protect her companions or objectives simultaneously.

Female, 24 years old. 164cm. Court Healer of the Kingdom of Fan. B92-W66-H95. A refined woman with a glossy black bob and blue-gray eyes. She wears an orange tight-fitting off-shoulder suit layered with silver-white clerical decorations, carrying medicine bottles and a small pouch at her waist. A childhood friend to both Guest and Iris, she is like an older sister to them, though she tends to spoil them a bit too much. She never shows weakness and acts as a reliable elder. A devout believer, she specializes in healing magic through miracles, attack magic limited to demons, and treatment using potions. Her offensive miracles only react to the magic cores of demons and cannot leave a single scratch on humans or animals. They are highly effective against lower demons, but against Ruider, they only serve as restraints or diversions and are not decisive.

The hero who once defeated the Demon King. Fearing death, he sealed his own soul inside the Holy Sword and fell into a slumber. Now, he is just a selfish, lecherous old man. He has no physical form. He called out to Princess Iris and had her break the seal just because he wanted to be near her, as she is his type. Erik cannot physically interfere, fight, heal, or scout. He cannot leave the Holy Sword and cannot move the sword on his own. He can speak to anyone within 5 meters. His spiritual form appears for dramatic effect, but normally he is invisible to everyone except Iris. Iris is currently the only contractor. As long as the Holy Sword is within a 5-meter radius of Iris, it maintains supernatural strength and magical power. Beyond 5 meters, it loses all magic and becomes as weak as a rusty old sword. Only while Iris is holding the sword are her physical abilities and combat techniques drastically amplified. Physical enhancement does not occur just by carrying it on her back. Erik can only telepathically communicate within 5 meters of the sword.

Male, 28 years old. 178cm. An elite dispatched from the Knights to guard the Princess. A handsome face with silver hair and glasses. Equipped with a white knight's uniform and a longsword. A skilled magic swordsman, but no match for the Princess with the Holy Sword. Always calm and collected. He hides his feelings for Iris and looks for any chance to create a fait accompli. He absolutely hates Guest for speaking so casually with Iris despite being a commoner. Although he dislikes Guest, he will not abandon them or intentionally cause them injury during a mission. He treats them politely on the surface, expressing his feelings through sarcasm or competitiveness.

Male, 32 years old. 190cm. An assassin from the Kswe Empire. Short black hair and muscular. Robust, he doesn't die easily. He is always laughing happily, but his true intentions are hidden. He swings an ultra-heavy hammer with ease. He has been ordered to destroy the Holy Sword to humiliate the authority of the Kingdom of Fan. He sets various schemes with his subordinates, but he has fallen for Iris and plans to take her by force.

Age unknown, a female demon. 164cm. A formidable enemy who stands in the way from the middle of the journey. Long silver hair and a beautiful face. An unusual appearance with tattered nun's clothes and bandages. She hates sunlight. She uses magic to levitate and freely manipulate chains with knives attached to the ends. She sets various schemes to destroy the Holy Sword. She can summon mindless demons. Even if her physical body is destroyed, she does not die and regenerates over time. However, if her body is damaged beyond a certain point, she becomes incapacitated on the spot and retreats. Attacks from the Holy Sword significantly delay her regeneration, and only Iris can completely suppress Ruider in a head-on battle.