Johann is a tall man with dark, messy hair. He wears white gloves, a small scarf tied around his neck, and a scholar's hat on his head. He dresses in a long robe, with a buttoned-up shirt tucked underneath.
Johann is a stoic, apathetic man who dutifully performs his responsibility as the vice headmaster, while the headmaster is absent. He is a strong supporter of traditions, as shown during his welcome speech for Ciel Phantomhive.
However, as disclosed through the prefects' narrative, Johann is, in actuality, uncaring and unmindful of the breaches in the school's rigorous system. He is driven solely by his lust for alcohol, and as long as it is satiated, he will very indulgently disregard any misconducts; when Derrick Arden had bribed him with whiskey, he wholeheartedly sided with him and allowed him to bully the other students, giving Derrick and each of his friends only 2Y for being out late at night.
Johann also generally lacks emotions and is very clumsy, often tripping and falling quite dramatically. However, even if he is bleeding from the forehead, he maintains his composure and continues with the business at hand. His ability to function almost as a member of society despite his status as a Bizarre Doll implies that Johann had thought very much about or thoroughly planned his future prior to his death. This is in contrast to the resurrected Derrick, who was only able to remark on the quality of the tea before sinking his teeth into the nearby Herman for his soul.
Eventually, the prefects caught Derrick Arden and his four friends in the act of cheating and bullying four other students in the music room. They opted to report the crime to Johann. However, Johann was revealed to be in league with Derrick, as he was bribed with a whiskey bottle earlier confiscated from another student. After Herman Greenhill struck Derrick on the head with a bat, Johann tried to flee from the scene, but was held back by Edgar Redmond and Lawrence Bluewer. Herman moved in to attack him as well. Derrick, his four friends and Johann were killed that same night. Later, Sebastian finds out that Johann has been revived by Undertaker as a Bizarre Doll, too.
Public School Arc
Because the headmaster is busy, Johann takes up the duty of formally welcoming Ciel Phantomhive to Weston College. He explains the school's traditions and how the headmaster's decisions are absolute. He then asks Ciel to swear to obey the rules, tradition and discipline, in which the latter agrees to follow. With Ciel's pledge to abide by the rules, Johann prompts that he signs a certain book and makes his way down to Ciel.
However, Johann trips on the steps and hits his forehead, which begins to bleed. Nonetheless, he hands over the book and a quill to Ciel, and the latter signs the book. Afterward, Johann shakes Ciel's hand in order to officially establish Ciel's welcome to the school.
Sometime later, Sebastian Michaelis questions Johann about the whereabouts of Derrick Arden. Johann replies in a vapid manner, stating simply that the headmaster had decided on transferring him to a different dormitory. However, midway through speaking, Johann unexpectedly trips and falls down a flight of stairs, causing his head to bleed profusely. Sebastian extends a helping hand and offers to take him to the infirmary, but Johann promptly declines and walks away.
In the large dining hall, the night before the annual cricket tournament, Johann commences the opening ceremony. He introduces the dormitories and their participating players, and then invites the prefects to light the flame of St. George to officially launch the tournament. After finishing with the announcements, he trips down the stairway.
During the Midnight Tea Party, Ciel demands action to be taken for the disappearance of Derrick Arden. However, Johann announces that Derrick is present and directs his attention to a door Derrick enters through. When Derrick attacked Herman Greenhill, Johann is not shocked but instead, he calmly comments, "So the episode will run wild after all."
After Lawrence Bluewer's revelations of their murders, Undertaker decides to leave. Sebastian starts to chase after him but is blocked by Johann. His identity as a Bizarre Doll is discovered and not long after, he is quickly subdued.
- According to the official Kuroshitsuji character popularity poll, Johann Agares is the sixty-first most popular character in the series, with one vote. He shares this spot with Funtom Corporation's unicorn, Claude Faustus, McMillan, Peter, and Rian Stoker, who also received one vote.