Lye Batenkaitos (ライ・バテンカイトス) was a Sin Archbishop of the Witch Cult, representing the gourmet aspect of Gluttony until his defeat and death in the climax of Arc 6. First introduced in Arc 3 interludes, he later served as a major antagonist in Arc 5 and one of the main antagonists of Arc 6, alongside his brother and sister. In the sixth arc's climax, Lye fought Ram and was subsequently decapitated by her.
He was perhaps one of the most mysterious and overlooked Sin Archbishops as due to the nature of his Authority, he wasn't held responsible for any Witch Cult attacks whatsoever. Accordingly, Lye didn't have any actual enemies that would direct their hate towards him and him alone. Throughout the years, he ate thousands of people, inheriting their memories and skills which he would use for his own benefit right to the very end in the Pleiades Watchtower, making him one of the most prolific fighters in the history of Re:Zero universe, mastering pretty much all known sorts of combat abilities and martial arts.
Lye Batenkaitos stood at around five feet and one inch tall, making him a fairly short youth whose height was comparable to the likes of Rem. Like his siblings, he appeared to be roughly twelve or thirteen years of age with a high-pitched voice that denoted his apparent youthfulness. His straight unkempt light-brown hair, that had tips drenched in blood and dirt, trailed down to his knees and fell over his face in a way that obscured his right eye. His diminutive and slender physique had a surprising amount of musculature to it and his dark skin was littered with a multitude of grotesque scars that varied from whip to bite marks. His most distinctive facial features were his repulsive emerald green eyes and fang-shaped sharp teeth that usually formed a sadistic smile.
Like the other Sin Archbishops, Lye's clothing deviated from the religious habit worn by most Witch Cultists. Much like his body, the Sin Archbishop of Gluttony's clothing was tattered and dirty. His primary piece of clothing was a skin-tight purple bodysuit that exposed his arms, bare feet, and chest and had horizontal pink stripes across it. Over the top of his bodysuit, he wore a tattered black cloak with red patterns that reached down to the ground. A pair of Witch Cult daggers were strapped to his forearms that served as his primary weapons.
In Arc 5, Lye fully showed off his body, revealing a multitude of grotesque and horrid wounds, ranging from whip marks to bite and scratch marks. He gave off an unnatural and bizarre aura; completely opposite from what you would expect from a child.
After finally using Solar Eclipse and breaking out of his shell, Lye took on a more monstrous and distorted appearance; an amalgamation of most of his victims. One could see body parts of Neiji Rockheart, Beli Heinelga, Dorkell and Rem among numerous others. His limbs were of different length, his head was of distorted proportions with a part of it belonging to the bald old man, part of it resembled Rem's and so on. Lye himself was unaware of this change.
Lye believed that everything came down to experiences, and the one who manages to get better knowledge is the one who enriches his life and wins over people, also remarking that knowledge is power and memories are bonds, ultimately concluding that this means that he was the greatest. Due to that, he also referred to himself as intellectual Sin Archbishop.
Unlike Roy, Lye also strongly believed that if the number of lives in the world is limited, then the amount of worthy food is limited, and would hence not miss a single chance of eating them. Lye remarked how Subaru is his "savior", as he is able to remember the people who have gotten their names eaten, pointing out how the forgotten feelings of rage and revenge were a source of dissatisfaction, but Subaru was an exception to this. Lye also seems to look out for Louis, pointing out how she may be happy if he was to eat Otto, Felt and Dynas.
Lye's fighting style was vastly different from his brother's, often giving his opponents a chance to "prove" themselves as being worthy of being his meal and liked to compete with them, before ultimately eating them and claiming their abilities for himself through Authority of Gluttony.
He strongly resented merchants, referring to them as "people who place prices on things and sell them to line their own pockets. They're dead people who place the values and opinions of people on a scale before calculating". Lye cared about the quality of the lives he ate, and frequently remarked on how he was not like Roy and won't be satisfied by eating just anything.
Also, the three spoke in a collective manner using us and we instead of first or third person.
Authority of Gluttony (暴食の権能 Bōshoku no Ken'nō): Lye was able to use the Authority of Gluttony until his demise.
- Gluttony (暴食 Bōshoku): Lye could eat the name and memories of their opponent. To eat a name, he had to touch them with his left hand, then licked the palm of the same hand as well as chant their full name. Things such as experience, talent, and the likes and dislikes of human relationships served as food for him, allowing him to take advantage of any and all abilities or memories his opponents had. However, if he ate a fake name, he became plagued with severe nausea, usually throwing up only seconds after.
- Those that had their names eaten had their existences erased from the world, destroying any human relationships along with negating any contracts with Spirits. Not even the people closest to them could remember a single thing about them.
- Those that had their memories eaten became amnesic and any characteristics they may have had are reset, effectively making them into a different person.
- Those that had both their name and memories eaten simply became a shell, and although they were alive, they no longer ate, excreted waste, or aged, putting them in suspended animation.
- Lye could not eat the same person twice until that individual gained enough new memories to establish a different sense of self from their old one.
- Lye could not eat the names or memories of non-humanoid beings, such as different animals, Demon Beasts or Earth Dragons.
- Eclipse (蝕): Eclipse was considered to be the trump card of gluttony and it also had two types; Solar Eclipse (日食 Nisshoku) and Lunar Eclipse (月食 Gesshoku).
- Lunar Eclipse allowed the holder to use the victims' memories and harvest their skills and knowledge. Lye used Lunar Eclipse to boost his physical strength and perform numerous martial art techniques including The Palm of the Fist King and the Leaper technique. It is worth noting that by eating a person's name and using Lunar Eclipse, Lye did not gain his victims' Divine Protections, Spirit Arts or Authorities. On top of that, Lye could also combine any number of memories and skills which would in turn allow him to create any sort of synthesized super-class technique he desired.
- Solar Eclipse, however, allowed the holder to harvest his victims' name and transform their appearance accordingly. Louis, for example, transformed into Neiji Rockheart and numerous other victims she and her two brothers had eaten throughout the years using her sibling's body. Originally, Lye never used Solar Eclipse as he didn't like the side effects of morphing into his victims; according to him, he felt like he was losing himself. After his fierce battle with Ram however, Lye was forced to use Solar Eclipse to morph into Dorkell in order to escape certain death and effectively overcame his fear of using the aforementioned Solar Eclipse, by finding a way to retain his own sense of self . Following that incident, Lye freely started using both Solar and Lunar Eclipse, greatly amplifying his fighting strength as by morphing into the original owner of a specific skill one plans on using, the effect will be much greater; by morphing into Dorkell, Lye was able to leap much farther and by morphing into Neiji Rockheart, his Palm of the First King attacks were much more devastating.
- Demon Beast Control: Because Lye, Roy and Louis possess the Witch Factors of Gluttony which were previously in Daphne's possession, they could direct Demon Beasts to attack certain areas. This is why the White Whale's attacks were coordinated with those of the Witch Cult. In Arc 6, Lye and Roy were able to get to the Pleiades Watchtower in half a day by commanding the Demon Beasts in the Augria Sand Dunes, and ordered them to attack the Watchtower. Despite his ability to control the White Whale and the Great Rabbit, even if Lye had help from his younger brother and Sister, they wouldn't be capable of controlling the Black Serpent, according to the author.
Master Class Fighter:
Through the accumulation of souls eaten, Lye gained any abilities his victims once had such as martial art techniques and magic. In turn, this had granted him extraordinary combat strength. He was able to overpower multiple strong opponents at once, as shown in Arc 6. At the end, embracing both Solar and Lunar Eclipse allowed Lye to use hundreds and hundreds of skills and attacks at the same time.
- Huma (ヒューマ): Lye created a shining water barrier that blocked other projectiles and sorts of magic. However, if the incoming magic was stronger than the shield it would get through it and damage Lye.
- El Huma (エル・ヒューマ): Lye formed and shot multitudes of ice spikes from his hands which easily pierced through human flesh and immediately vanished on impact.
- Palm of the Fist King: A powerful strike that ruptured a person's internal organs, as well as outright, destroyed physical objects like swords. It could also bypass mana based defensive techniques. The move originally belonged to Neiji Rockheart.
- Leaper technique: This technique allowed Lye to move with extreme speed undetectable by the naked eye, essentially allowing him to leap behind his opponents or avoid extremely precise and quick attacks. Due to the extreme speed, it seemed like he was teleporting around the battlefield. He was also capable of utilizing it vertically, making it appear as if he was flying. This move originally belonged to Dorkell.
- Carnivorous Beast: This ability allows Lye to strengthen his body which gives him two advantages: he could withstand powerful attacks and strengthen his limbs to deliver devastating blows. With this ability, he was able take a hit from Emilia's ice spear and come out unscathed and deliver a retaliating punch that was said to be as devastating as getting hit by a car. This ability formerly belonged to Beli Hainelga.
- Ice Brand Arts (アイスブランドアーツ): Whenever Lye successfully ate Emilia's "name" during the events of Arc 6, he copied her Ice Brand Arts with the help of his Lunar Eclipse. This technique allowed Lye to instantly conjure ice made weapons which he could use and freely manipulate in close-quarters combat. The weapons were very sturdy and were even capable of withstanding heat.
- Invisible Wind Blade Technique: During Arc 6, Lye used an unnamed wind blade technique that he claims came from a samurai. He could use this to set wind blades at fixed points in space, unable to be blown away by even Ram's Wind Magic. He was also able to jump off these blades to either escape or launch a sneak attack.
Creation: Louis has stated she and her brothers can create life with the usage of her Witch Factor of Gluttony, just like how Daphne created the Demon Beasts four centuries ago. However, Louis has also stated she and her brothers had no reason to do so, hence they never followed through the idea. While all of this was strictly stated by Louis, it's safe to assume Lye was also capable of creating life through his Witch Factor of Gluttony.
- Witch Cult Daggers: Lye skilfully used two standard Witch Cult daggers that were wrapped around his arms. He was able to masterfully deflect extremely precise attacks, block strikes that would shatter any sword and easily overpower even the strongest knights.
- Witch Cult's Gospel (魔女教徒の福音): As a member of the Witch Cult, Lye was the owner of a copy of the Witch Cult Gospel. Each Witch Cult Gospel was a replica of the Book of Wisdom, a book that had been in the possession of the Witch of Greed Echidna. The Book of Wisdom would provide exact details of future events concerning the Witch of Greed, essentially bestowing Echidna with a form of precognition. Unlike the original Book of Wisdom, the Gospels of the Witch Cult were imperfect replicas, meaning that, although they detailed the future of its owner, the events conveyed were subject to change and the information provided was often up for interpretation. The Gospels took the form of small black books that could only be read by their owners.
- Lye, like every other Sin Archbishop (with the exception of Stride Vollachia), is named after a celestial body. "Baten Kaitos" was the traditional name used for Zeta Ceti, a star located in the Cetus constellation. The word was derived from the Arabic term بطن قيطس (batn qaytus), which translates to "belly of the sea monster."
- He was "Gourmet" for his obsession with preparation before a meal.
- In episode 26, Lye can be seen using the Leaper technique to avoid Rem's ice spears.
- In the novels, he was first seen using this technique in Arc 5.
- In the Web Novel version of Arc 4, Lye mentioned that he could create a new Hakugei if he was given another 400 years. However this conversation has been cut from the Light Novel.
- In a Q&A, the author stated that if Daphne and Lye Batenkaitos, Roy Alphard and Louis Arneb were to fight, it would most likely end in a stalemate.
- According to the author, if Lye was to be transported to modern Japan, without his authority he would be a shoplifter.
- In a Q&A, the author said that Lye did wine tasting in his free time, though this might've been said in a joking manner.
- "However, in the battle with Ram, he almost died, and in order to survive, Batenkaitos broke out of his shell the moment he turned into ‘Leaper’ Dorkell using Solar Eclipse. He had found a way to maintain his sense of self while in his Solar Eclipse form that he had originally been afraid of losing." Arc 6 Chapter 83; Section 2
- "“You know the Three Great Witch Beasts? It’s said that those, are monsters created by the owner of our Witch Factor long before us. We too, can do something similar. We didn’t do that because there wasn’t really any meaning in doing so…… but, you see.”" Arc 6 Chapter 75