Heine Wittgenstein is the titular royal tutor and the main character of the series.
Though Heine is a grown man of around 40, he's often mistaken for a child due to his short stature and young appearance. He has dark salmon-red hair styled neatly and pale skin. Heine has an unusually expressionless face and facial expressions of rage and surprise are expressed more through his eyes rather than through any other aspect of his face. He has large reddish-amber eyes and he wears thin silver-rimmed glasses in a rectangular shape. One of the most recognizable aspects of Heine's appearance is a black cap with white and gold accented lining with a white tassel attached to it. He always wears a long black jacket reminiscent of a single-lapel trench coat with white and burgundy accents. A strip of burgundy fabric lined with white is fastened to the coat with gold fasteners, each end fastened under a lapel so that it goes around the back to form a semi-circle. The sleeves are also lined with burgundy and white fabrics, although the burgundy stripe is thicker than the white. The collar and lapel down are lined with white as well. Under the coat, Heine wears a dark brown vest over a white collared shirt and a gold-tipped black tie. He wears simple, black fitted pants and black heeled ankle boots.
Heine rarely shows any type of emotion and is incredibly stoic. He acts polite towards everyone at all times, even when insulting them. He seems harsh and cold but is actually very empathetic and understanding of people. He's intelligent but does not flaunt it. The only time he loses his composure is when someone mistakes him for a child.
Not much is known of Heine's past in the manga. He and King are close friends, as confirmed by the fact they are on first-name basis, with no honorifics. Count Rosenberg discovered that Heine used to be a tutor at the Maria Vetsera church for children before coming to the palace, but his past before that is unknown. He was actually a volunteer tutor at the church. He has rewarded a meal each day for volunteering at the church. It's implied that he used to be a violent man due to the fact that the King told him to use the skills of the "old him" to defend his sons.
Later it is known that the King used to sneak out of the palace when he was young, and got his pocket watch stolen by two street children who were reprimanded by a younger version of Heine, and gradually, the two became close. Heine could not read, which was revealed when he said he did not know what the brand of white wine he had in his hands was.
During the Harvest Festival, the King, who was then Prince Viktor slipped out of the palace again to meet Heine, but did not know that the entire palace was in an uproar due to his disappearance. Troops of guards were sent out to look for Viktor, and catch the kidnapper they supposed had kidnapped him. One troop found Viktor with Heine, and when Heine dropped Viktor's pocket watch which Viktor had given him previously to buy warm blankets and clothes for the street children Heine took care of and the guards saw the royal crest on it, they assumed that Heine was the kidnapper automatically.
As Heine and Viktor were running away, one of the guards leveled his gun barrel at Heine to shoot him, but Viktor halted, taking the shot for Heine by leaping into range of the rifle, taking a severe wound near his heart. The guards instantly surmised that Heine had used the Prince as a shield, and labeled Heine as a true felon. Upon seeing Viktor lying in a pool of blood on the ground, Heine saw red, snatched up a wooden beam and proceeded to attack the guards, snatching the rifle from one of the fallen guards to attack the rest, while Viktor pleaded in a weak voice for Heine to stop.
When Heine eventually heard Viktor, he came to his senses and fell to his knees, crawling to Viktor as he passed out, calling out his name desperately, even when the recovered guards swarmed around him, arresting him and dragging him away. Heine was in prison all the time for kidnapping and attempted murder of the Prince, but never pleaded his innocence, and only prayed that Viktor would recover. After a very long time, Viktor made his appearance before Heine, having recovered his consciousness, smiling at him and saying that he had come for him, and Heine saying tearfully that he was glad he was alright. Heine was pardoned when Viktor told the then king the truth, and Viktor was shortly afterward crowned as king. Heine became a tutor at a church Viktor built for street children to stay in, and became the Royal Tutor on this condition: That if his past was revealed, he would leave instantly.
After all this was revealed to the current princes, they were told from the King that Heine has resigned from his position as Royal Tutor.
Heine was shown to have battle skills and knew how to handle a gun. This attributes to the fact that he was once a thief.
After Count Rosenberg dropped Heine off at the castle, he makes the area fill with tension by saying, "What I mean to say is... You are not from our side, are you?" Heine replies by making a stern look. When the Princes mention about a criminal being in the Palace, Heine decides to teach them a lesson and questions them what their reactions would be if the so-called 'criminal' was Heine himself.
- People mistake Heine as a child plenty of times
- Heine hates when people call him tiny, little, small, or midget (synonyms)
- There's a mysterious photo of Heine and one other person that has appeared twice in the manga. Prince Kai finds the person to be familiar. (Spoiler Alert: It's the first prince, Prince Eins)
- In the manga, Heine states in his thoughts that Princess Adele is young enough to be his daughter.
- Later in chapter 74, it is revealed that Heine is also a Kvel, a minority group that resides in the Kingdom of Granzreich.
- Heine is naturally messy and his room is filled with piles of books and other such things.
- Heine's artistic ability is atrocious
- "Instead of judging others based on rumors and gossip articles, I must look and feel for myself. You cannot know anyone without coming face-to-face with them"
- (to Kai Von Granzreich) “If you wish to make a good first impression, a smile is an excellent way to begin.”
- “2nd hand information is entirely unreliable.”
- “You cannot grow if you always run away from reality.”
- “One must never think they know someone after little to no time with them.”
- “A teachers task is to nurture hope, not harm the heart.”
- “A person can only truly learn once they realize how little they know.”
- “Before quitting something you want to do, you should always explore alternative solutions.”
- “A smile is a communications tool that surpasses all borders and languages.”
- "You need a lesson."