Draculan, also known as Drakulon, appears in the 23rd episode of the original Giant Robo series, titled The Cosmic Vampire. He is a distinctive antagonist who combines the traits of a traditional vampire with the scale of a giant kaiju, serving as a direct threat to the Unicorn organization and its young leader, Daisaku Kusama.

Draculan is a humanoid alien and a member of the BF (Big Fire) organization, led by Emperor Guillotine. In his standard human-sized form, he disguises himself as the elderly, unkempt keeper of a local village shrine, concealing his true nature beneath a white robe and using a long cane. This guise allows him to operate secretly within the community. His true appearance in this smaller form is a hunchbacked figure with a blue, bat-like face, long pointed ears, two prominent fangs, green skeletal-looking hands, and shaggy white hair. When he chooses to grow to giant size, he adopts a more elaborate Eastern European medieval style of clothing and wields a sword and shield in combat.

Personality-wise, Draculan embodies the cunning and predatory nature of a classic vampire. He is deceptive, using a fabricated story about a distressed woman to lure victims into a trap. He speaks with an unearthly echo in his human form, and in his giant form, he communicates through screeches and hisses, reflecting his monstrous nature. His primary motivation is to convert all of humanity into compliant vampire servants, a goal he pursues on behalf of his affiliation with the BF gang. He demonstrates a strategic mind, attempting to use hostage situations and coercion to force Daisaku to turn Giant Robo against its allies.

In the story of the episode, Draculan serves as the central monster-of-the-week. After a Unicorn agent is found drained of blood, Daisaku and his colleague Minami are sent to investigate the area. They soon encounter Draculan, who reveals his plan to turn them and all Earthlings into his servants. When the situation escalates, Draculan captures the agents and holds them for conversion, forcing Daisaku to call upon Giant Robo. The ensuing battle makes up the episode's climax, where Draculan's vampiric powers are pitted directly against the mechanical might of the giant robot.

Key relationships are defined by his allegiance. He is a subordinate of Emperor Guillotine and a member of the BF gang, using their resources to further his vampiric conquest. His main adversary is Daisaku Kusama, whose quick thinking and resourcefulness consistently counter Draculan's plans. He creates a small army of vampire servants from the local populace and even converts a Unicorn agent, turning former allies into enemies.

Draculan does not undergo significant character development, as he is a villain created for a single episode. His role is to present a unique magical and biological threat that stands in contrast to the more technological enemies Giant Robo usually faces. His defeat is brought about by a classic vulnerability, demonstrating that Daisaku must think outside the box to overcome supernatural foes. Daisaku remembers the legendary weakness of vampires to the symbol of the cross, and under his instruction, Giant Robo poses in the shape of a cross and conjures a Flaming Cross attack. This magical assault is super-effective against Draculan, who is terrified by it and ultimately destroyed, ending the reign of his vampire servants.

His abilities are firmly rooted in vampire mythology. He can drain the life force, specifically the blood, from living humans, turning them into his obedient vampire servants. He is impervious to standard weapons like bullets. He possesses the power to change his size from a human scale to that of a giant, and he can alter his appearance to that of an old man to hide in plain sight. Unlike some traditional vampires, sunlight does not pose a weakness to him. However, his one notable and fatal vulnerability is the Cross.