Known as Demon Overlord (大魔王; Daimaō/Władca Demonów) or Lord of All Everything Fearsome (Władca Wszystkich Strachów) he is an overpowered creature overthrowing kings and destroying empires. Stronger than Goku, stronger than Saitama. Worse than pure evil and more sinister than satan himself; he is a fanatical catholic. Crusader and Conquistador, he devours sinners and pagans. Once destroyed the Universe. He is the leader of Fellowship of Badass, the final boss of the every universe, not to be defeated. Cecylia’s beloved one.
He was originally a human, but he turned into a yōkai against his will, yet Cecylia loves him notwithstanding that. It was only thanks to her that Tadeusz maintained his human heart. Still, when Cecylia was murdered, he went berserk and brought forth chaos and destruction.
As a human he was a completely innocuous dweeb by nature but also a knight serving directly under Adam the Holy Knight as he was his vassal. Tadeusz’s personality changed dramatically after he became a yōkai (though he remained a bishōnen).
His third name and family name have been buried within darkness of history, yet there are speculations that his second name is Bartłomiej. He possesses a àholy sword (sabre) named End of Enlightened Ages (Koniec Oświecenia), though he can defeat any army with his bare claws. He is venomous but biting people is not his aesthetics.