"However, I’m also a little bit interested in you. If you want to complain to me, my treat. Or you can refuse if you think it’s a trap. But it doesn’t matter either way."
Leon Cromwell, to Rimuru
Leon Cromwell (レオン・クロムウェル Reon Kuromuweru), formerly a True Hero, is one of Eight Star Demon Lords and the only Hero to be publicly known as a "Demon Lord." He is also called the Blonde Demon. He is one of the three true Heroes of humanity but left them after several incidents to join the faction of Demon Lords.
He has long platinum gold hair, blue narrow eyes, a well-defined face, and skin so white that it is almost transparent. He is so beautiful that he is often mistaken for a woman at first glance. Despite his young appearance, he is three hundred years old.
He doesn't take men for partners. Even among women he only goes for the ones he desires. His skill of evading the point is rather superb. Leon can also being perceived as cold-hearted, as he made Shizu suffer due to being possessed, though he did it to save her life. Despite his calm and collected appearance, he was actually a bit of an airhead, and the type to step in conversational landmines.
Leon was originally a world traveler and Chloe Aubert's childhood friend, who he shared a close sibling-like relationship with. They were caught in the accidental occurrence of a dimensional distortion but Leon appeared in the world alone. He decided to search for Chloe and obtained the Hero's egg due to his desire to protect her.
He is the last born Demon Lord, the human "Demon Lord" Leon Cromwell. He with his overwhelming magical power rules over his increased number of Majin, he identifies himself as the Demon Lord of the frontier.
One of the Demon Lords was furious with him, the Demon Lord Kazaream had waged war against him. But he was beaten by Leon instead. It was also by Leon's own hands. Due to this, Leon's "Hero's egg" hatched and he awakened as a true hero. In response to the situation, the other Demon Lords, not knowing that Leon is a hero, recognized him as a new Demon Lord.
He summoned Shizue Izawa out of Tokyo firebombing and made Ifrit possess her, which brought her not only inconsiderable suffering, but on the other hand, she'd certainly die hadn't he summoned her, and Demonic Possession was the only way to save her from the horrific injuries she already sustained.
- His subordinates are reminiscent of the Super Sentai Warriors due to their color scheme.
- He is one of the youngest demon lords.