Dilandau Albatou is a primary antagonist and the commander of the elite Zaibach military unit known as the Dragon Slayers. Physically, he appears to be around fifteen years old, standing 175 centimeters tall with a slender, androgynous build. He has pale skin, silver-white hair, and garnet-red eyes, and he is keenly aware of his own attractive appearance. He pilots a distinctive red guymelef, first the Alseides model and later the Oreades, both equipped with flight capabilities, stealth cloaks, and powerful weaponry like a flamethrower and a liquid-metal Crima Claw.

In terms of personality, Dilandau is defined by his absolute ruthlessness, impulsiveness, and a deep-seated love for battle, destruction, and fire. He is sadistic, megalomaniacal, and almost entirely lacks self-control, compassion, or conscience. His vanity is a significant character flaw; he takes immense pride in his beauty and becomes fixated on revenge after receiving a sword cut on his right cheek from Van Fanel, the king of Fanelia. Unable to leave the wound alone, he obsessively picks at it, preventing it from healing and ensuring it leaves a permanent scar, which further unhinges him. His mood is volatile, shifting from manic glee to apathetic dazes, and his insubordination is a constant problem for his superiors, though he demonstrates a cleverness for following the letter of an order while violating its spirit, such as attacking from a fortress when ordered not to leave it.

Dilandau's primary motivation is the pursuit of battle and the destruction of his enemies. While his official mission from the Zaibach Empire is to capture the legendary guymelef Escaflowne and its pilot Van, his personal goal quickly narrows to killing Van to avenge the scar on his face. This rivalry becomes an all-consuming obsession. Despite his cruel and abusive treatment of his subordinates, whom he frequently slaps and berates, the Dragon Slayers remain fanatically loyal to him. However, when Van eventually kills most of the Dragon Slayers in a furious battle, Dilandau loses his tenuous grip on sanity, becoming catatonic and only coming to life on the battlefield.

The character's role in the story is deeply tied to a major plot twist. It is revealed that Dilandau was originally a gentle young girl named Celena Schezar, the sister of the knight Allen Schezar. Kidnapped by the Zaibach Empire as a child, she was subjected to experiments by Emperor Dornkirk's Fate Machine, which transformed her body and mind into the bloodthirsty persona of Dilandau. A beastman named Jajuka served as her caretaker during this time and acts as an emotional anchor for Dilandau. As the series progresses and Dilandau's mental state deteriorates, the alterations begin to break down, causing him to involuntarily switch between his male Dilandau form and his original female form, Celena, who exists in a naive, childlike state.

Over the course of the narrative, Dilandau develops from a dangerously unstable but effective warrior into a completely broken figure. His sanity erodes with the death of his Dragon Slayers and the psychological strain of his false identity. In the climactic battle, Van prepares to deliver a final blow, but Jajuka sacrifices himself to save Dilandau. With his last words, Jajuka urges Dilandau to return to being the gentle child he once knew. Overcome with grief and the realization that he is now alone, Dilandau permanently transforms back into Celena, and the personality of Dilandau Albatou ceases to exist. As a warrior, Dilandau is exceptionally skilled in swordsmanship and guymelef piloting, capable of fighting on foot or within his machine with great proficiency.