Yoichi Saotome continues his internal battle with the demon of the Black Demon Series. Haunted by his sister's death, he cannot find the courage to overcome the demon and use its power for his own. Meanwhile, Yu and Kimizuki continue to fight the newly formed Man Eater with their new Demon Weapons. As the battle continues, Guren orders the two to kill Yoichi, to which they both refuse to do. Yu then drops his weapon in a final attempt at bringing back his friend. Having seen enough, Shinoa pleads with Guren to stop the chaos and take matters into his own hands. Guren then shouts encouraging words to the possessed Yoichi, granting him a brief moment of realization.
After conquering his anxieties and fears, Yoichi overcomes the demon's influence and regains control over his body. He then runs and jump-hugs Yu. Guren tells the new recruits to not become taken over by revenge. He then tells them that their first task shall take place in Shinjuku which, coincidentally, Mika is heading to.
The night that Yoichi's sister died is replayed in its gruesome, heartbreaking detail before Yoichi's eyes. She knew vampires were in their house, and she hurriedly hides him under her bed before they break into the room. Her murder is done at the hands of Lacus Welt, and Yoichi actually hears a vampire call Lacus by name as they run back to their headquarters at the summons of their Queen. Yoichi's sister is left lying unceremoniously on the floor, bleeding and lifeless as her empty stare meets with his. She then speaks right to him, letting him know that she is showing him memories of his past. The demon had apparently taken the form of his sister, likely so as to wound his heart in the most wicked way available.
Standing in the same white void of his mind with his demonic sister, Yoichi is told that the demon has found him wanting. There were no particularly strong feelings in his heart that the demon found appealing, and she feels that he simply is unworthy to command her power. It is then that the demon approaches him, threatening to possess him so that she can simply avenge Yoichi's sister in his place. With no apparent willpower to resist, Yoichi is taken and the demon awakens in control of his body in the underground ceremony chamber.
The scene plays out just as it did at the end of the previous chapter, and the demon surveys the room and sees her four targets. Guren orders the boys to slay Yoichi, and to do so without actually calling on their demons. As they had zero experience using them, he knew that letting them truly cut loose with those things would not end well. However, the two obviously wouldn't have the heart to go that far, as they are at ends with the thought of gutting someone whom was not only their friend, but someone Yu had gone to lengths to protect in the past. Reluctantly, and after protesting this idea to an uncaring Guren, they brandish their blades and lunge at the demon. Explosive arrows rain down all over the chamber, and it's everything the boys can do to avoid getting hit. Closing the distance, Yu knocks the bow from Yoichi's hand. He celebrates briefly, thinking that separating the user from the weapon would release the demon's hold on Yoichi, but Guren yells that the demon is in Yoichi, which only meant the demon couldn't shoot arrows at Yu at that point. Kimizuki's blade comes within a couple inches of Yoichi's throat, but he falls back with Yu and tells him that Yoichi's beyond help. Shinoa also tries to convince Guren that this order to kill their friend was too unreasonable. Amidst all the arguing and fighting, Yu tosses his sword aside and puts all his trust in Yoichi to break free, trying to plead to the boy that had to watch his family die the same as Yu did. Even Guren chimes in, telling Yoichi to come out of that bed and fight alongside his friends. In the deepest corners of his heart, Yoichi crawls out from beneath his bed and claims the power of his demon weapon, regaining control of his body. He lunges into Yu's arms, hugging him tight as tears streamed down his face.
With Yoichi joining his friends in ownership of Cursed Gear, Guren told them to toss aside any petty notions of revenge and instead live to protect the new family they each have in each other. However, Yu isn't quite ready to let the past go just yet. Guren then announces that it is time to put the newest members of the Moon Demon Company on the front lines, starting with investigating the Kansai region due to reports that vampires plan on retaking Shinjuku. Incidentally, Mika is among the company of vampires whom are on this exact mission for the Kansai region, each of them unaware of this inexplicable reunion.
List of characters in order of appearance:
Manga panels provide a visual overview of the events of Chapter 7 with depictions of the characters, Seraph of the End world and scenarios.