Regulus Corneas (レグルス・コルニアス) was a Sin Archbishop of the Witch Cult, representing greed until he was defeated by Reinhard van Astrea, Natsuki Subaru and Emilia. He was one of the primary antagonists during the fifth arc of Re:Zero.
Regulus is described to have a "normal" appearance, with features that aren't handsome yet not ugly. He has a thin body along with white hair that isn't long nor short, nor arranged in a strange way. He has gold eyes and appeared to wear a blue earring on his right ear. In the Web Novel (Arc 3 Interlude "Let's eat"), he wears black clothes that follow the same concept, making him ordinary enough that people would forget about him soon after spotting him. In the light novel his clothes got changed to white with less simple concepts.
During the wedding of the fifth Arc, he made an appearance in a more formal outfit. The respective colors of his outfit were white, gold and slightly blue, the same color scheme as his regular outfit.
Regulus was talkative, and tended to describe himself as "unselfish" despite representing greed. He would often go on and on about plausible theories, though in actuality he forced his own selfishness on others and tried to justify it. If his opponents say something that goes against his opinions, he would find unreasonable faults in them, becoming angry while accusing them of "violating his rights".
He was extremely prideful and viewed himself as a "divine being" or "the most satisfied existence in the world" as seen when Reinhard and Subaru intruded his wedding. He disliked getting needlessly involved with others. He's hot-tempered, as shown when he attacked Subaru the moment the latter doubted his words and mocked him for his hypocrisy. He was shown to have no regard for titles, as seen in Arc 5, when he mocked Reinhard, calling him "a moniker of some guy who knows of nothing but swinging a sword". Ultimately, his talkativeness and naiveness were what killed him. He gave away his secret to Subaru who then figured out his Authority of Greed and gave Reinhard a chance to finish him off. He never realized his "sins", not even in his last moments when his life flashed before his eyes. His view of the world was distorted and tainted with hate and disgust.
More than 100 years ago, Regulus used to live with his family. His father was an alcoholic but tried to be a good father, his mother who complaining about bad earnings but apologized for it occasionally, and his two brothers who were sometimes mean to him but gave him their share of their meal if he accidentally spilt his. At some point in the past, Regulus obtained the Witch Factors of Greed, and subsequently killed his entire family, then village and then everyone in the surrounding cities. He broke his childhood love's mind, slaughtered her family and forced her to marry him, thus making her become his first of many wives.
He was also a Sin Archbishop of the Witch Cult even 100 years in the past and participated in the attack of the Elven village in Elior Forest along with Pandora. He had a one-sided battle with Petelgeuse Romanee-Conti who just took in the Witch Factors of Sloth, cutting both of his hands off in a relatively short time. Just before he was about to deal the finishing blow by smashing Petelgeuse's head open, Fortuna interrupted him, which greatly angered him. When Pandora calmly asked him to spare Petelgeuse's life, he lashed back at her and threw dirt at her, killing her instantly. Soon after, Pandora used her Authority of Vainglory to erase her death and proceeded to teleport Regulus back to his mansion, reverting the damage he has done to Petelgeuse and Elior Forest.
Fifteen years before Subaru's arrival, Regulus single-handedly took down a heavily fortified Vollachian city of Garkla, housing thousands of soldiers and the Vollachian hero Kurgan. It is said that at the time, Witch related artifacts were being auctioned in the city.
Interlude 2 - "Let's Eat"Edit
A couple of months after Subaru's arrival, Regulus was taking a stroll at Lifaus Highway and encountered a military convoy that was returning to the Capital , after the successful White Whale Subjugation. The first dragon carriage rammed into him and got disintegrated to the point one couldn't tell which remains belonged to the dragon and which ones were the driver. Crusch and Rem ordered their dragon carriage to trample him as well, but managed to successfully escape once Rem realised how futile it is. After that, Regulus began with his speech, complaining how inhuman their actions were and how rude it is to not answer someone's question, to which Crusch responded with her One blow One Hundred Felled technique. Regulus then proceeded to use the wind created by his hand to sever Crusch's right hand, leaving both Crusch and Rem flabbergasted. Soon after, Rem realized something else is amiss as none of the soldiers were coming to help them, and spotted Ley Batenkaitos drenched in the knights' blood. Ley and Regulus then proceeded to introduce themselves as Sin Archbishops of the Witch Cult, telling Rem their reasons for assaulting the military convoy. Regulus then started talking about his rights and desires, stating how he hates fighting. Rem ignored his words and attacked the two Sin Archbishops resulting in Ley eating her name and memories, effectively erasing her from everyone's minds except Subaru's.
A little over a year after Subaru's arrival, Regulus went to the Watergate City of Priestella to marry a new wife. He encountered Natsuki Subaru and Emilia in the city's streets, setting his mind on marrying her. Soon after, a fight between Sirius, Emilia and Subaru broke out, giving Regulus an opportunity to save her and abduct her, but not before erasing Subaru's left leg and inviting him to his wedding. On the day of his wedding with Emilia, Subaru and Reinhard successfully deciphered his Authority of Greed and killed him by smashing him deep underground which damaged a nearby water canal, resulting in him drowning soon after.
Authority of Greed (強欲の権能 Gōyoku no Ken'nō): Regulus was able to use the Authority of Greed until his Witch Factors were taken by Natsuki Subaru following his death.
- Stillness of an Object's Time (物体の時間の静止 Buttai no Jikan no Seishi): The user can stop the time of themselves or anything they're wearing, touched, or even their breath. This stops any interference from outside and only allows the user's interference outwards. This negates any attack against the user. The atmosphere released from the stillness can cause shockwaves and it can enable the user to travel at extremely high speeds. Normally, multiple uses of this ability can be deadly as the user's own heart also stops, however it can be circumvented when combined with another of the Authority of Greed's abilities.
- Small objects imbued with Stillness of an Object's Time create devastating and destructive attacks. Regulus stops the time of pebbles, gravel or dirt and throws them at an enemy. These objects will travel through anything and anyone, resulting in the object or a person's destruction, as seen when he managed to hit Pandora and Subaru's left leg. He is also able to bombard a whole street with water droplets, destroying everything in its path.
- Apart from pebbles, dirt, gravel and other objects, he can also create an invisible wall of death by stopping time of his breath as seen in his fight against Reinhard or stopping time of the air produced by his hand's movement, effectively creating an invisible blade of air that will cut everything in its path.
- Lion's Heart (獅子の心臓 Shishi no Shinzō) or Small King (小さな王 Chīsana Ō): The user merges their heart with one of the people of his kingdom, or in other words any woman that the user has confirmed to be their wife. With this, the user can use the effects of Stillness of an Object's Time as long as they wish to. As it is only a pseudo heart, even if the merge is destroyed the only aftereffect is that the user bears the burden again. Any conditions or effect area haven't been shown.
- As of a hundred years ago, Regulus had 78 wives, and as of Arc 5 he is mentioned to have had 291 wives in total. However, according to Sylphy, 238 of those wives were killed, leaving only 53 alive.
- Regulus, from Latin, means "Little King".
- His namesake is a reference to the star Regulus, which is the brightest star in the Leo constellation.
- Regulus was mentioned to be a young man 100 years ago.
- To this day, he is the only person that managed to kill Reinhard.
- Regulus is the strongest Sin Archbishop of the Witch Cult.
- Regulus owns a mansion, however it's location is unknown. In Ayamatsu IF Natsuki Subaru and Elsa Granhiert burn his mansion to the ground in order to get rid of his Authority and kill him.
- Despite him being the strongest Sin Archbishop of the Witch Cult, he never managed to kill Natsuki Subaru.
- The author stated that due to his Authority, if Subaru wasn't present in Arc 5, Reinhard would not be able to beat him.