Black Baby Beel

, is a powerful entity created by Zenjūrō Saotome’s Demon World training radio.

Appearance
Being an exact replica of the original Baby Beel, his physical appearance does not change much, save for a blackish purple coloration and no visible eyes. He retains Baby Beel’s trademark hair, pacifier, and is also nude.

Personality
Like Baby Beel, he speaks in nonsensical babbling and the typical baby language; however, since he is a demon radio carbon copy, his voice sounds distorted. Similar to the real Baby Beel, he is very curious, having chased a rabbit during a training session with Oga. He, like Beel, also gets bored easily, such as when Saotome attempted to entertain him by buying him a Shougi set.

Saint Saint X’mas Arc
During the Saint Saint X’mas competition, Black Baby Beel joins Saotome and Ikaruga while they are competing, hiding within a wool hat that Saotome wears to disguise himself. When the two adults are about to face off against Oga and Hilda, Saotome loosens his hat to show that Black Baby Beel is inside. Later, Black Baby Beel and Baby Beel meet each other again and start comically fighting one another atop their respective male figures’ heads; while they fight, Black Baby Beel slaps Baby Beel and sends him flying backwards. Afterwards, both infants participate in the subsequent match with their respective pairs, neither of which doing much aside from observe while clinging to their male figure’s upper body.

Powers & Abilities
Being exactly the same as Baby Beel, Black Baby Beel possesses the Demon Lord’s hidden potential, which he can use at full power. He is shown to be very strong, as he was able to headbutt Oga into a boulder.

Techniques

 * Black Baby Beel Cry: Just like Baby Beel, Black Baby Beel retains his crybaby personality. After getting his head stuck in a hole in a tree, he got upset and proceeded to cry. This cry retains the similar electric element of Baby Beel’s, but at a much larger scale: it ends up burning the tree and creating a large chasm in the ground.
 * Flight: In desperation to escape from Oga and to locate the wayward rabbit, Black Baby Beel reveals he has the ability to fly by flying over the chasm he had created before.
 * Tape side change: After a given set of time, Black Baby Beel ”changes tape sides”. Since he is an entity created by a radio, he possesses the characteristics of being a ’tape’. Side A shows his weaker form, but side B shows him at full power.
 * Lord of the Flies form: Black Baby Beel’s true form in battle. After Oga apparently captures him, he "switches tape sides" and takes on this form. However, Oga easily defeats him by simply ignoring him, leading Black Baby Beel to throw a confused tantrum and eventually give up.

Zenjuro Saotome
After training in the Mapputatsu Mountains, Saotome had expected Oga to defeat Black Baby Beel. Since he was not defeated and still existed, Saotome could not find it in him to destory him or leave him to live into the mountains, so he decided to take the demon home with him. Saotome acts as his caregiver and keeps him under his teacher’s desk.

Beelzebub IV
Being the direct subject he was created from, Black Baby Beel is fond of ’himself’. However, both show a rivalry due to one instance of them arguing for milk Oga was preparing (resulting in the discovery of Super Milk Time). When Saotome reveals he had decided to keep Black Baby Beel, Black Baby Beel comically grabs Baby Beel and tosses him over.

Tatsuya Himekawa
In the anime episode Black Baby Beel Has Grown, Himekawa ’kidnaps’ him due to his striking resemblance to an old statue his great-great-grandfather had found which gave him good fortune. Due to its disappearance, the Himekawa family grieved its loss. He believed Black Baby Beel was the statue and decided to keep him. Black Baby Beel’s feelings to Himekawa seem to be mutual, as he is shown to hand some luck over to him.