He is the next leader of the JIDA. In the novels Kureto often reminds Shinya that he is his superior and he should not double cross Hiiragi family. He suspects Shinya may be a vampire spy because he is close to Guren. He says he trusts Guren and sends Guren on an extremely dangerous mission to Nagoya. A member of the prestigious Hiragi family.
Guren's former lover and Shinya's former fiancée. He agrees to pretend to be her fiancee after she reveals she is in love with Guren. She kills Shinya and the rest of Guren Squad and she becomes the demon in his sword. Shinoa Hiragi's elder sister.
A higher-ranking member of the JIDA. A member of the prestigious Hiragi family.
Shinya meets Shinoa when he is sixteen and is friendly towards her due to her relation to Mahiru. A squad leader in the Moon Demon Company. Guren uses Shinya and Mito Jujo to help train her briefly before the attack on Nagoya. Shinya works with her and Narumi's squads in Nagoya. Although Shinya spectates her betrayal for allowing Mikaela to escape, it can later be seen that he still places his trust in her.
Leader of the Japanese Imperial Demon Army as well as the Hiragi family, he adopted Shinya into the Hiragi family as a fiancé for Mahiru. They do not have a good relationship.
A member of Guren's squad since he was 16 back in high school prior to the apocalypse. He enjoys making fun of Guren, and Shinya and he often team up to do so. A member of the prestigious Goshi family. Shinya and Norito appear to good friends and often team up to annoy Guren.
A member of Guren's squad since she was 16 back in high school prior to the apocalypse.
A newbie soldier, who Guren experimented on. A wielder of a Black Demon. A member of Shinoa's squad, and a hothead, who challenged Shinya to a fight. He knows little about the Hyakuya Sect. When Yūichiro tried to make his attempts in rescuing Guren from Crowley and his aides, Shinya commanded that they retreat under Guren's final command.
Commander of the Moon Demon Company. Shinya and Guren have been friends since high school. Guren loved Mahiru Hiragi, Shinya's fiancée. When he learns Kureto gave Guren a suicidal mission in Nagoya, Shinya joins with Guren to help him. Shinya enjoys teasing Guren. Both Guren and Shinya made the main attacks on Crowley and after several attempts of trying to attack. In their attempts to retreat, Crowley still manages to catch up to them in a playful manner. Upon being captured by Crowley, Guren placed Shinya in charge and gave his final command that he and the other troops head to the rendezvous point at the airport. When Shinya meets a possessed Guren, he furiously tries to get him back into his senses. He then realizes that Guren has been possessed by Mahiru. Three months later, an imprisoned Shinya receives news from Aoi that Guren and Kureto will be returning sooner. He is also informed that Guren wishes to speak to him upon his return. Later it is revealed by Ferid that Guren revived his whole squad, including Shinya. After Guren confronts him in cell, Shinya says he no longer will be able to forgive Guren.
A member of Guren's squad since she was 15 back in high school prior to the apocalypse. She appears to be tsundere toward Guren, but he is not interested. A member of the prestigious Jujo family.
Kimizuki's little sister and possesses the Seraphim of the fifth trumpet. She brings forth the demon Abbadon and wrecks the airport's landscape. In the end she is defeated by Yūichirō as the King of Salt with the second trumpet.
A newbie soldier Guren experimented on. A wielder of a Black Demon. A member of Shinoa's squad. He gets tricked when Shinya attacks them from behind during a match to train Shinoa.
Leader of his own squad, he refuses orders from Shinya and makes the decision to abandon the mission and head back to rescue Guren.
The personal assistant to his older brother Kureto. She controls the chains that are used to absorb the blood of both vampires and humans alike for the Seraph. Shinya addressed her as Kureto's pet dog and questions her about her sister.
A soldier of the Moon Demon Company. She works under Shinoa as part of her squad. A member of the prestigious Sangu family.
A newbie soldier Guren experimented on. A wielder of a Black Demon. A member of Shinoa's squad. He gets tricked when Shinya attacks them from behind during a match to train Shinoa. Shinya coaches him on sniping. Both of them take on the sniping tasks during the Nagoya war.
A member of Guren's squad since she was 16 back in high school prior to the apocalypse. She does not speak often.
An extremely powerful vampire, who gets Guren by the neck during the battle at Shinjuku. Until Shinya snipes him, that is. Fortunately, he escapes the battle with minor injuries.
A seventeenth Progenitor and noble serving under Ferid's faction. Their encounter is on the battlefield in Shinjuku, then later again at Nagoya. She along with Horn and Crowley chases after Shinya as he tries to escape with Guren.
A powerful vampire that fights at Ferid's side. In Nagoya after capturing Guren, Shinya appears to rescue him. He chases after them in an almost playful manner. Due to his outrageous power, Guren ordered Shinya to take command to lead the rest of the troops to the airport.
He stabs Mikaela, but can later seen that the two as well as Shinoa's Squad aid each other in escape.
A servant to Lucal Wesker. He is sacrificed as a meat shield after Yoichi snipes at him with Shinya by his side.
A seventeenth Progenitor and noble serving under Ferid's faction. Their encounter is on the battlefield in Shinjuku, then later again at Nagoya. She along with Chess and Crowley chases after Shinya as he tries to escape with Guren.
Shinya works with Shinoa and Narumi's squads to exterminate him in Nagoya. Along with Yoichi they make the first move on Lucal by launching sniper attacks. However, these were blocked by Lucal as he tossed Esther Lee to take the shots.