Hartmann Bezelheim is a character from the anime Princess Lover!, where he serves as the primary antagonist. He is a prominent figure from the nation of Hazelrink, known as the most successful businessman in the country and a chief trading partner with the Arima company. Hartmann is introduced as the fiancé of Princess Charlotte Hazelrink, a role that establishes his connection to nobility and his initial position as a seemingly respectable member of high society.

In terms of appearance and manner, Hartmann is often seen wearing glasses and has a noted tendency to make flashy and extravagant entrances, such as parachuting from a blimp onto a school rooftop. This flamboyant behavior contrasts sharply with his true nature. On the surface, he presents himself as a straightforward and honest individual, but beneath this facade lies a cunning, treacherous, and manipulative personality. His primary motivation is a deep-seated hatred for Teppei Arima, the main protagonist. It is revealed that Hartmann is the one who murdered Teppei's parents, and he seeks to kill Teppei as an act of vengeance. His broader goal is to destroy the Arima conglomerate and its heir, pushing Teppei and his grandfather, Isshin Arima, into ruin.

Within the story, Hartmann's role is that of the main villain orchestrating events from behind the scenes. He fakes his own death during an assault at Arima Hills, which was carried out by an army of rebel soldiers led by his red-haired secretary, Josephine, with whom he is having an affair. This deception allows him to kidnap Princess Charlotte and further his plans against the Arima family. His key relationships are defined by duplicity. His engagement to Charlotte Hazelrink is a political or social arrangement he betrays by carrying on an affair with Josephine. His relationship with Josephine is one of co-conspirators, though it proves volatile, as he eventually shoots her for deviating from their plan. His central conflict is with Teppei Arima, whom he despises and seeks to destroy.

Throughout the narrative, Hartmann experiences a notable development. After a climactic confrontation on a train, where Teppei delivers a passionate speech urging him to reform, Hartmann attempts to commit suicide by detonating the train's locomotive. He is ejected from the explosion by Teppei's butler, Alfred, and dumped into a river. As he drowns, he smiles, acknowledging that Teppei was right. However, he survives this ordeal, and in his final appearance, he is shown at Josephine's bedside, leaving his ultimate fate ambiguous. Regarding abilities, Hartmann is a highly successful businessman, demonstrating significant influence and resources. He is also a skilled manipulator and planner, capable of staging his own death and executing complex schemes of revenge and corporate sabotage.