A young demon from the Unico manga series created by Osamu Tezuka and Sanrio. Beezle/Mr. Demon (known as Akuma-kun) is the son of Lucifer who lives in deserted island filled with rocks known as "The Demon of Solitude". Debuting in the manga's final chapter called "Unico and Solotude", Unico first encounters Beezle after his lightning attack intended for Unico backfires and ends up hurting himself. Originally antagonistic towards Unico, he refuses to become his friend unless he has Unico's own horn and is later seen roughhousing with him. After rescuing him from drowning, Unico gives him his own horn after realizing that Beezle loved him (which he refuses to admit).

In the English dub of "The Fantastic Adventures of Unico". Beezle was voiced by Cheryl Chase (best-known as the voice of Angelica Pickles from Rugrats). In the movie, he helps Unico rescue Katy from Baron Ghost/Baron De Ghost near the film's third act.