Ilotte Venomania becomes one of the Five Dukes of Beelzenia. He meets and marries the noblewoman Nylpho.
Nylpho Venomania aborts a child concieved with a servant.
Karchess Crim is born.
Yufina Marlon is born to the king and queen of Marlon.
Lilien Turner is born as the daughter of a baker.
A baby boy is born to Ilotte and Nylpho with a small face-like blemish on his right cheek. Nylpho, upon seeing the deformity, believes it to be a result of her previous abortion and commits suicide. Ilotte, blaming the boy for Nylpho's death, locks him up in the basement.
Maylis Beelzenia is born to emperor Jupitaire Beelzenia.
Irina, now going by I.R., finds the Demon of Lust's sword and takes Haru Netsuma as her medium.
Gumina attempts to break off the engagment with Sateriasis. She learns that he was planning to assassinate Cherubim, as he thought Gumina had fallen for him.
December: Cherubim learns of Gumina's engagment to Sateriasis, and approaches her at a party. In an attempt to protect him from Sateriasis, Gumina harshly rejects him.
In a fit of rage, Cherubim slaughters the entire household the next day. Before he can kill himself due to the guilt, Cherubim is approached by I.R., who intended to have Ilotte contract with the Demon of Lust. I.R. instead offers the sword to Cherubim, and he contracts with the demon by stabbing himself in the chest. Sateriasis accidentally wipes his own memory while attempting to wipe the memories of the sole witness to his crime, making Cherubim believe he is his brother Sateriasis.
Sateriasis becomes the new Duke of Asmodean. He begins secluding himself due to his lustful urges.
January: Sateriasis wanders into Lasaland during the New Year's Festival and collapses due to his lack of sexual contact. Sateriasis is rescued by Lukana, and he hires her to make him a new wardrobe, having her stay at the mansion while fighting his lustful urges.
Lukana rejects Sateriasis' love while he returns her home, triggering his memory of Gumina's rejection, the massacre, and his agreement with I.R. Sateriasis chases after Lukana and brainwashes her, only to have his demonic form be spotted by the peasant Mikulia. He attempts to brainwash her as well, but is unable to due to the Demon of Sloth in her. Sateriasis moves Lukana down to the basement and begins continually having sex with Lukana to control his lustful urges.
February: I.R. tracks Mikulia down and she joins his harem voluntarily as she sees him as her "demon prince".
Sateriasis wipes the people's memories of his interactions with Lukana and Mikulia.
Sateriasis brainwashes Lolan Eve and Mirigan Adi and adds them to his harem.
Gumina and her father Classke visit and discuss the disappearances of women around Asmodean, and arrange to have a date between the two bethrothed to help recover more of Sateriasis' memories.
March: Sateriasis goes on his date with Gumina and learns about "his" older brother. He determines that Gumina had fallen for Cherubim instead of him and that was what caused him to go on his massacre.
Angered, Sateriasis goes on another massacre, this time at the Glassred Mansion. He then brainwashes both Carol and Gumina and adds them to his harem.
Sateriasis adds Hakua Netsuma, the older sister of I.R.'s medium, to his harem.
Yufina gives a Marlon family heirloom, a golden key pendant, to her favorite retainer and her secret partner, Karchess Crim, before leaving for the Beelzenian Empire.
Sateriasis massacres Yufina's entourage and abducts her into his harem.
Karchess begins investigating the disappearances.
Sateriasis adds Sonika Sonic, Lazuli Blue, and Priema Soap to his harem.
April: Sateriasis and I.R. search for a vessel of sin that turns out to be a false lead. While there he meets Lilien.
Sateriasis woos Lilien. When she realizes he's the abductor of Lukana he brainwashes her and forcefully adds her to his harem.
Rajih, Lilien and Lukana's childhood friend, confronts Sateriasis over his abduction. In response, Sateriasis heavily wounds him and Rajih collapses. Rajih later claims that the Duke is responsible for the abductions, but is branded as a lunatic.
Sateriasis adds Mewtant Lusha, Tette Cetera, and Rio Neja to his harem.
Sateraisis seduces and uses the spy Neruneru Nerune to abduct Maylis, who then seduces.
I.R. gains an interest in Lukana due to her purple dream ability, but Sateriasis refuses to let I.R. use her.
Rajih is approached by Karchess to learn information about Venomania.
Lolan dies one morning after Sateriasis spends time with her, leading him to enchant the elderly ex-doctor Annlee Sweets to monitor the women's health. Annlee then discovers that Lukana, Maylis, and Mikulia have all been impregnated by the duke.
I.R. gives Mikulia a Clockworker's Doll she's been working on, and the Demon of Sloth migrates from Mikulia to the doll.
Karchess meets up with Elluka and learns from her that the pendant is a vessel of sin, and agrees to hand it over after defeating Venomania. The two make a plan to approach the duke later.
Elluka visits the mansion, and soon after I.R. attempts to flee with the sword and Lukana. Sateriasis confronts her, however, and she agrees to leave Lukana at the mansion.
Karchess deviates from the plan and forms a contract with the demon of wrath and learns to transform the key into a knife.
Karchess visits the mansion disguised as Elluka, and pretends to be wooed by Sateriasis' magic. While dancing with his new bride in the basement, Sateriasis is suddenly stabbed in the chest by the golden knife. Sateriasis collapses as Karchess triumphantly reveals himself. As Karchess searches for Yufina, the rest of the women, freed from the hypnosis, flee the mansion. The lust magic leaves his body as Sateriasis' face returns to it's natural deformed state. He recalls that his lost memories, and realizes he never confessed his feelings to Gumina. He is unable to speak and watches her leave breathlessly.
Mikulia returns to Abito. After giving birth to Sateriasis' son she flees the village and eventually works as a prostitute in Lasaland.
Maylis carries Sateriasis' child to term; as the daughter was illegitimate the imperial family wouldn't acknowledge her as a family member, so Maylis entrusts her to the childless Baron Conchita and his wife.
Lukana leaves Mystica with Lilien and Rajih, intending to start a new life with them and her child. I.R. begins pursuing Lukana and the group continues to run.
Gumina leaves from Asmodean to Elphegort with her father; she then begins civil work in the Elphegort government.
Lukana and her friends approach Elluka with their problem. Elluka swaps bodies with Lukana to take it out of I.R.'s grasp and make her stop chasing the four.