- "I'll sink to whatever the depth. If through this―I can attain you, Gumina―"
The Venomania Event was the name given to the mass abductions of women throughout the Beelzenian Empire, carried out by Duke Sateriasis Venomania. Through his demonic powers, the Duke of Asmodean enchanted, collected, and sexually defiled women for over a year before his untimely demise.
- "I can't attain anything. Not in the past, or in the future."
Born to the Duke of Asmodean in the Beelzenian Empire, a boy was locked away by his father and neglected for years due to his deformity; his only friends were his younger half-brother, Sateriasis, and the daughter of Marquis Glassred, Gumina. The boy was later freed from his confinement and made a servant to the Venomania household. Although reviled by the other servants for his deformity, "Cherubim" remained close with Gumina and Sateriasis, having fallen in love with the former. Suspicious of Cherubim's relationship with his fiancée, Sateriasis planned to assassinate his brother.After overhearing Sateriasis and a servant discuss the assassination plans in December of EC 135, Gumina worried for Cherubim's safety and decided to treat him coldly and throw off suspicions. Having learned of Gumina's engagement to his brother, the deformed young man attempted to confess to her. With Sateriasis watching them, Gumina attempted to ward off her fiancé's suspicions by publicly scorning Cherubim.
Broken-hearted, Cherubim slaughtered his entire family the next day. Immediately afterwards, the man was approached by I.R. while he attempted suicide. The sorceress allowed Cherubim to steal his half-brother’s face, and then encouraged him to make a contract with the Demon of Lust to give him its many powers, including the power to brainwash women. In return, Cherubim was expected to aid her in future dealings. The young man accepted the offer and forged a contract with the demon.
- "Don't get me wrong, Lilien... I'm not imprisoning them against their will. They all want to live as part of my harem."
- ―Duke Sateriasis Venomania[src]
Changing his face to that of his brother, I.R. quickly taught the man how to use a ritual to wipe people's memories within an area. After accidentally wiping his own memory in the process, I.R. used her sources to have "Sateriasis Venomania" become the new Duke while he was determined to be the "sole survivor" of his household's massacre. Following Lasaland's New Year Festival of EC 136, the Duke encountered the visiting Lukana Octo in town and befriended the tailor, tasking her with tailoring some clothes for him.
Twenty days later, shortly after Lukana's departure for Mystica, some of Sateriasis' memories reawakened and he reunited with I.R. again. Using the Demon of Lust's power to take on demonic form, Sateriasis pursued the tailor to a nearby forest en route to Abito. Capturing and brainwashing the woman, Sateriasis was spotted by Mikulia Greeonio while working there. After failing to brainwash her with his spell, the startled girl fled. Sateriasis returned home with Lukana and I.R. in total secrecy, keeping her in his basement while they made love for days.
A week later, in February, Sateriasis and I.R. visited the nearby village of Abito and found Mikulia in the village outskirts. With the peasant convinced he was her "prince" coming to take her away, the Duke returned home while I.R. stayed behind. At midnight that night, Mikulia sneaked out of her house and was led by I.R. to the Duke's mansion, becoming the second member of his harem and they made love for days. Afterwards, he seduced the famed dancer, Lolan Eve, at her theater in Lisa-A and later the famous fortune teller Mirigan Adi in Evnemi, pleasuring himself with the different girls daily.
Around this time, Princess Maylis Beelzenia assigned Marquis Glassred to discreetly investigate the sudden string of disappearances throughout Asmodean. In March, Duke Venomania infiltrated the Glassred Mansion in his demonic form and slaughtered every guard and servant he came across. After brainwashing her bodyguard, Carol Shields, Venomania captured and brainwashed Gumina, wiping the girl's memories of Cherubim. Following Marquis Glassred's subsequent breakdown, Princess Maylis assigned Marquis Ferdinand to take over the field investigation into the disappearances.Sateriasis later brainwashed Hakua Netsuma after coming across her. Soon after, the Duke successfully abducted Queen Yufina Marlon while touring Asmodean with Marquis Donald. To keep the issue from becoming an international scandal with Marlon, the Beelzenian Imperial Family reported the Yufina was too ill to return home. By early April, the unsatisfied duke brainwashed and kidnapped Sonika Sonic, Lazuli Blue, and Priema Soap.
That month, Sateriasis visited Mystica with I.R. in order to obtain a supposed vessel of sin in the Misty Mountain ruins. While visiting the town, Venomania seduced his guide to the mountains, Lilien Turner, and discovered the alleged vessel of sin was just a regular magic tool. Afterward, the Duke massacred the entire Ferdinand estate and began courting Lilien over the next several days. After being discovered to have kidnapped her childhood friend, Lukana, the Duke brainwashed Lilien and brought her under his control.
Venomania then encountered her other friend, Rajih, who witnessed his depravity and demonic power. Briefly battling with Rajih in his demonic form, the duke defeated him and left Mystica once the town's memories of his visit were erased. As the year progressed, he added Mewtant Lusha, Tette Cetera, and Rio Neja to his harem, his harem numbering fifteen by the summer. During that same summer, Maylis recruited Count Karchess Crim of Marlon to assist in the investigations.
After a month of investigation, Karchess pursued a lead concerning the Ferdinand family massacre and Lilien's disappearance. Interrogating the nephew of the deceased marquis at Mystica, Karchess learned of Rajih's ravings about Duke Sateriasis' involvement. He then recruited the drunkard and learned of Venomania's involvement, forwarding his potential lead to Maylis. After Maylis' spy, Neruneru Nerune was enchanted by Venomania, the Duke used her to help him capture and brainwash the Empire's third princess.
Growing increasingly absorbed in his harem, the duke's lustful and sadistic nature became more and more warped. Around the same time, some of the women experienced increasing strain from the brainwashing they were receiving. Required to take their life energy through sex to fuel his powers, he eventually began taking the lives of some of the women; after exchanging information with him, Lolan Eve was discovered dead the next day and buried by I.R.
- "As I thought, you're the culprit, aren't you, Duke Venomania!"
"... You're... a... man...!?"
"It was the magnificent girls' clothes, wasn't it?"
- ―Karchess and Sateriasis[src]
The Marlon count infiltrated the Duke's mansion and approached the inviting Venomania. During their embrace, Karchess stabbed Sateriasis with the Golden Key after it transformed into a knife. The duke collapsed and the Lust magic infused in him from the Demon leaked from his wound. With his power broken, the women were freed of his spell and fled from the estate. He died shortly after due to his injury.
The women killed by Venomania were later discovered by imperial officials although most were able to return their families unharmed. Levin professors of the Held sect soon established Venomania as a demon and many of the women faced intense discrimination for their relationship with the Duke. Among those, many of the women were pregnant with his children and were identified for spreading his lineage and scorned for generations. Due to Venomania's parentage, a handful of the women gave birth to children that acted as carriers for HER Syndrome.
For arbitrarily murdering one of the Five Dukes, the Beelzenian Empire began hunting Karchess after he fled with Yufina and eloped. With their affair uncovered, Yufina's husband, King Martius, also began hunting for the pair. Two years after Venomania's death, the two staged a coup to remove Martius from power and establish a "legitimate Marlon country", with no ties to Beelzenia.
Lukana and Lilien later began travelling east to Akuna with Rajih and Lukana's child with Venomania. Following the birth of the Duke's daughter, Princess Maylis gave the child to Baron Toy Conchita to hide the relation. Gumina, having fled with her family to Elphegort, became the nation's first female prime minister and an advocate for women's rights in politics. Within a year after the incident, Mikulia ended up in a brothel in Lasaland with her and Venomania's child and later died.
Centuries later, the novelist Yukina Freezis wrote a Freezis Fairy Tale based on the event entitled "The Duke and the Four Women" Hundreds of years afterward, the celebrity Scherzer attempted to recreate the incident, kidnapping countless women and locking them in his mansion's basement before selling them into the slave trade until his crimes were discovered.
The citizens of the Beelzenian Empire were baffled by the sudden disappearances throughout the region, each girl seeming to have simply vanished without a trace. Nobles who attempted to look into the incident were usually unsuccessful, and close friends and relatives to the victims became increasingly distressed by their absence.
Due to Venomania's power over memories, few citizens recalled him at the site of each disappearance; because of this, none suspected the duke of his involvement and believed he was merely investigating, along with the other nobles in the Empire. Even after Venomania's death, many details about the event remained unclear to the public, including the exact number of women abducted into his harem or Venomania's true identity as Cherubim.
In Asmodean history, many citizens venerated Venomania as a hero for his exceptional tenure as duke; this veneration lead to Venomania having a significant impact on Asmodean culture, adopting military and cultural traditions connected the Venomania family dukes and the man himself. In other parts of Evillious, particularly among Levin believers, Venomania was instead reviled as a demon.
Because of their bodily association with him, women who had been confirmed part of the duke's harem were feared and publicly shunned; this discrimination extending to all their descendants and continuing for many centuries. It was only by the tenth century EC that Venomania's crimes and legacy faded from public memory, although still remembered in history by some.
- The Venomania Event is the first major incident caused by the Demons of Sin; fittingly, the Duke would also indirectly cause the next major Sin-related incident, fathering Banica Conchita's ancestor.