Main ; : :Akihito is a second-year high school student with short blonde hair who is an immortal half-youmu, the offspring of a youmu and a human. He has the ability to heal quickly from any wound albeit still experiencing pain. Due to this Mirai uses him as practice to help overcome her fear of killing youmus. He is a member of the Literary Club. He has an attraction to girls with glasses, as shown by his spontaneous compliments to Mirai, whom he develops romantic feelings for, as well as being disdainfully teased for it by Mitsuki. If Akihito's physical human body finds itself in a severe weakened state, his dormant youmu half emerges, physically changing his body into a hideous feral appearance which then proceeds to go on a rampage. Akihito's youmu half is extremely powerful, able to easily overwhelm supernatural cages and barriers that attempt to contain it in addition to having enough destructive force to physically devastate whatever landscape surrounds it. Akihito implies that because of his youmu half, the Nase clan are not exactly his friends but instead people who are tasked with watching him should his youmu-half ever go berserk and killing him if necessary. Following a youmu transformation, Akihito falls into a state of depression due to almost killing Hiroomi in a past rampage. Akihito's youmu half holds the greatest destructive power of all youmu and is referred to as "Beyond the Boundary". ; : :Mirai is a first-year high school student with short, light pink hair styled into a
bob, and wears red-rimmed glasses, leading Akihito to call her a 'bespectacled beauty', much to her dismay. She has the ability to manipulate blood, which is unique even within the scope of the Spirit World. Overuse of her ability results in severe
anemia while at the same time it causes her to feel isolated and seemingly attempts suicide by jumping off the roof of the high school until she is saved by Akihito. She is summoned to kill Akihito but ends up harboring feelings for him. She is often ridiculed due to her constantly posting about the misfortunes in her life on her blog and Twitter account. She usually uses the phrase, to describe most situations, particularly at remarks made by Akihito. Despite her cursed blood lineage, she was adopted by the Inami clan and befriended their daughter, Yui Inami whom she killed out of fear after Yui was possessed by the Hollow Shadow—an act of which Mirai is deeply regretful and hence gave root to her fear of killing. Her signature weapon is a carmine colored sword formed out of her blood. ; : :Mitsuki is a second-year high school student with silky, dark hair. She is the younger sister of Hiroomi and Izumi and the President of the Literary Club. She enjoys teasing Akihito, such as claiming to be his childhood friend (in actuality, Akihito first met her in junior high; the OVA revealing it was the same incident in which his youmu half nearly killed Hiroomi). Although she calls her brother Hiromi a "pervert" and calls him "aniki" (respected older brother) to sound less informal, she really adores him and holds him very dear to herself. Her clan governs Spirit World Warriors in their area. Izumi instilled in her the belief that Spirit World Warriors are to be alone all their life, due to their duties and therefore resulted in Mitsuki missing out on experiences with her peers while growing up. She has a rodent-like youmu called "Yakiimo" as a familiar. Like her brother, Mitsuki is capable of setting up cages. ; : :Hiroomi is a third-year high school student who is also Mitsuki's brother. He has black hair in a bowl-cut and wears a scarf at all times due to his supernatural powers that make him cold. He is also a member of the Literary Club. Hiroomi adores his sister Mitsuki and likes having her call him "Onii-chan", and also has a habit of teasing Akihito and affectionately calls him "Akkey". He is proficient in setting up cages or barriers that prevent youmu from entering a protected area. His supernatural abilities make him extremely sensitive to the cold which not only causes him to constantly wear a scarf and also warm his fingers in Akihito's armpits much to the latter's annoyance. His back is severely scarred due to having to restrain Akihito's youmu rampage in the past, which almost resulted in his death.
Spirit World Warriors ; : : A rather skilled Spirit World Warrior. She is usually referred to as "Nino-san" and works as a teacher at Nagatsuki High School, in addition to Spirit Hunting. Despite her beauty, she always finds herself turned down by men. ; : : Akihito's mother and a Spirit World Warrior. She is constantly traveling and sends Akihito a postcard to check up on him every so often. Akihito describes her as being a "free-spirited"
avant-garde thinker in addition to possessing an eccentric personality and is thus ashamed of her childlike behavior. This is shown during Akihito's elementary school's Parents' Day when she sat at a student's desk while wearing a panda costume and participated in the class. ; : : The eldest daughter of the Nase clan. She usually has a calm demeanor despite having a malicious undertone. She has the viewpoint that youmu are no different from crops or farm animals and exist solely to provide her clan with a livelihood. Like the rest of her clan, Izumi is proficient in setting up barriers. She possesses a type of freezing ability while her signature weapon is a dual-tipped spear. She has a past connection with Miroku and also harbors a youmu within her body—which she tries to keep from the rest of her clan. ; : A silver-haired girl who was pursued during the Spirit World Warrior-slaying incidents. Her signature weapons include an automatic pistol and revolver. She also possesses the ability to suppress the power of an Interrogation Officer. She had an incident in the past with Miroku. ; : Mirai's childhood friend. He has a puppeteering ability.
Observation Department ; : : The main antagonist of the series and an interrogation officer from the Spirit World Warriors' Observation Department. He has the ability to instantly kill a youmu by simply focusing on it. He harbors a youmu within his own body, granting him special abilities. ; : An interrogation officer. ; : An interrogation officer. She has the ability to manipulate the weight of objects.
Others ; : : An appraiser of youmu. Her appraising business is camouflaged as a photo shop to normal humans. Her true form is that of a powerful multi-tailed fox-like youmu but usually takes the appearance of a human. She is also capable of setting up cages and barriers. ; : : An anime original character, Ai is Ayaka's 16-year-old sister who manages the appraising shop when Ayaka is unavailable. She is a cat-like youmu, with the ability to shape-shift into human form. ; : : The deceased daughter of the Inami clan. She was the only one in her clan who treated Mirai with kindness but was ultimately killed by Mirai when she became possessed by the Hollow Shadow. ; : : An anime original character, Sakura is the younger sister of Yui Inami. She hates Mirai for Yui's death and tries to kill the former as an act of revenge, but later realizes her true feelings for Mirai were clouded and forgives her. She has a tendency to be lazy at times. Sakura's spiritual powers are practically non-existent hence she fought using a spear courtesy of Miroku which absorbed the power of youmu stones. ; : An information gatherer. He has the ability to directly link his mind to the Internet to obtain information. ; : Sophomore at Nagatsuki High School. She wears a large ribbon on her head. Her signature phrase is "Hey!". ==Media==