Horrorman appears as a skeleton wearing a long, tattered purple shirt featuring a pair of crossed bones on the chest. His skeletal structure leaves his teeth perpetually visible and emphasizes prominent kneecaps and cheekbones. A recurring character in the Anpanman universe, his name originates from a pun: "horror" sounds similar to the Japanese expression "hora," meaning "look here!" or "look at me!" He frequently uses "hora" in his speech.

Despite his spooky appearance, Horrorman possesses a notably cheerful, clumsy, and goofy personality. He enjoys deliberately trying to scare others, though his efforts consistently fail due to his inherent silliness. Conversely, he often frightens people inadvertently through accidental actions or his mere presence. While generally inclined to be nice, he displays a lack of concern for potentially hurting others' feelings and cheerfully admits to traits like being a "back stabber and a liar."

His primary special attack is the Bone Boomerang, performed by removing one of his bones and throwing it as a weapon. Horrorman typically associates with the primary antagonist Baikinman and Dokin-chan, frequently joining their schemes. However, his alignment with their villainous objectives is inconsistent, and he does not always fully participate. He harbors unrequited romantic affection for Dokin-chan, often leading him to stalk her. His presence extends to various settings, including an underground ghost town inhabited by other spooky entities.

Background information suggests a possible existence predating the current era of life in the Anpanman world. One theory posits he might have been a shinigami (grim reaper) during a time when Earth was a completely lifeless desert, before the arrival of the "stars of life" that revived the planet. This theory suggests he could have lost his memories during that barren period, explaining his current state and disconnect from a traditional role associated with death.