TV Special
Description
Bathin de Emuna Alaindelon, a transdimensional demon serving the Great Demon Lord's kingdom, bears a full name signifying his noble demon lineage but prefers the shortened Alaindelon. His appearance strikingly recalls Freddie Mercury, mirroring the singer's hairstyle, facial hair, and flamboyant mannerisms. He possesses a muscular physique and typically wears casual outfits like sweatshirts with boxer shorts, though he readily adopts other attire such as school uniforms or swimwear as needed.

Alaindelon radiates a comical eccentricity, often striving for seriousness undermined by his perceived incompetence in ordinary tasks. While lacking conventional strength, he exhibits remarkable durability. He shows little concern for hiding his demonic nature in the human world, openly employing his dimensional transport power by dramatically splitting his body open—an act consistently inducing panic or disgust in human observers. This primary ability allows instantaneous travel between dimensions or within the same world. He transports others by enveloping them within his form and releasing them at the target location, frequently shouting "TRANSFER!!!" during the process. This power provides vital strategic mobility and rescue capabilities for the series' protagonists.

His initial appearance finds him floating down a river, feigning death, where Tatsumi Oga discovers him. Beelzebub IV emerges from his body, initiating Oga's role as the infant's caretaker. Surviving this encounter, Alaindelon becomes a frequent presence interacting with Oga and his friend Furuichi, eventually moving in with Furuichi after declaring him a "noble person." He later assists Hilda in diverse tasks, from household chores to intelligence work. He investigates supernatural threats at Ishiyama High School, observes battles involving Oga, and attempts to capture a mysterious figure instigating conflicts, though the target escapes using a Teleportation Jewel. Learning of Furuichi's life-threatening injuries during the "Mobichi Arc," Alaindelon reacts with urgency. Donning samurai armor, he transports Furuichi to safety alongside Lamia for medical treatment, displaying profound emotional distress over Furuichi's condition. Presumed fatally wounded in a demon world attack, Alaindelon survives and later participates in cross-dimensional communications concerning threats to the Demon Lord's kingdom.

His relationships include deep devotion to his daughter Angelica, prioritizing her safety even in peril. He idealizes Furuichi, addressing him as "Furuichi-dono" and persistently voicing admiration, though Furuichi usually finds this unsettling. With Oga, he maintains a pragmatic working relationship, frequently using his transport power to bypass the 15-meter distance limit between Oga and Beelzebub. He collaborates closely with Hilda, vocalizing her unspoken thoughts and asserting her hidden faith in Oga's capabilities despite her denials. Notable quotes include his enthusiastic greetings to Furuichi, declarations like "V for Volleyball is V for Victory," and his signature teleportation shout. His name derives from the French actor and entrepreneur Alain Delon.