How Not to Summon a Demon Lord

Takuma Sakamoto was a shut-in gamer who achieved renown as the Demon Lord in Cross Reverie, a MMORPG, for his overwhelming gear and skill.

After awaking to hands filled with breasts, Diablo follows Shera and Rem to register as new members of the Adventurer's Guild. While Shera is identified as a level 30 Summoner by the guild, Diablo's level proves too high for them to measure.

The Warrior Emile, defender and ally of all women, challenges Diablo to a fight.

Rem, Celestine, and even Emile struggle in their battle against Gregore's sudden attack. Meanwhile, Diablo and Edelgard confront each other on the Bridge of Ulug.

The Kingdom of Greenwood demands that Faltra City hand over Princess Shera. If they refuse, it will lead to war, so Diablo meets with Galford, the Lord of Faltra City, and accepts a quest to prevent war from breaking out.

While Greenwood's demands remain unmet, Diablo and the girls visit a slave market to see if they can learn the magical secret of the Enslavement Collars.

The following day after Prince Keera's visit, Shera suddenly bids farewell to Diablo while they're preparing potions. Unable to stop her from leaving, Diablo holes up in the inn, consumed with regret. Rem is unsettled to see him so negative, too.

Diablo squares off with Prince Keera's Summon, the Force Hydra, a monster he has never faced before.

Alicia returns to the Imperial Capital to give her report on the incident between Faltra and the Kingdom of Greenwood. There she encounters the Paladin, Saddler.

The night of the Demon Lord's resurrection arrives at long last. Rem finally reveals to Shera and Alicia that the Demon Lord Krebskulm's soul is sealed within her. Together, Diablo's party heads for Starfall Tower, where Edelgard awaits.

Diablo's party returns to Faltra with the newly resurrected Klem. On their way back from visiting Celestine, Rem and Klem suddenly get separated from Diablo and Shera, with Alicia having led them both astray.

The Demon Lord Krebskulm has awakened due to Alicia's betrayal. Diablo stands alone against Klem, her mind consumed by hatred. Shera races to Rem's side. An army of Fallen led by Edelgard marches on Faltra, and the curtain rises on their final battle.

Diablo inadvertently rescues the priestess Lumachina Weselia from an assassination attempt. As Lumachina had been praying when Diablo appeared she now believes Diablo is God.

When the group arrives in Zircon Tower City, a child named Horn offers to be a guide to the dungeon; the description confirms it is Diablo's dungeon. Later, a monstrous sand whale attacks the city and Diablo tries to fight it, but requires the help of Batutta and the city's leader, Fanis Laminitus.

Lumachina and Rem are drugged and abducted by Batutta and his maid, Shiliu. Horn spied on them and warns Diablo and Shera.

The group arrives at Diablo's dungeon and have to go through several rooms filled with mazes, monsters and lava.

Diablo saves an unconscious Horn and sacrifices his shirt and cape to make a fire. Rem, Shera, and Lumachina get through several floors of the dungeon only to run into Gewalt, who attacks them. They are interrupted by a massive black dragon who attacks them all.

Zircon Tower City's defenders are no match for Varakness' army. Varakness attempts to force Fanis to marry him. Diablo takes offense to Varakness saying he is working for a Demon Lord, so his group, including Rose, teleport to the battle. Diablo, Shera, Rem, and Rose then battle the army while Lumachina heals the injured with Horn assisting her.

Lumachina asks Diablo to accompany her to the royal capital, so he decides to stop by Faltra City on the way. Diablo`s group is worried about Klem and Edelgard after such a long time apart, and Sylvie informs them that they`re at a bakery. Apparently the Fallen, Edelgard, had started a part-time job. Curious, Diablo and the others go to investigate...

Diablo and his group arrive at the royal capital, Seven Wall, but the guards stop them at the gates. That explosive situation is resolved by the imperial knight, Alicia. She was awaiting their arrival and leads the group to an inn. That night Diablo reveals to Alicia that the church is out to kill Lumachina.

As Horn feels torn between escaping and wanting to rescue her friends, a tiny goddess appears and says she can substantially raise her levels.

After Diablo incurs heavy damage rescuing Lumachina from Europa's destructive attack, he asks her to cast a spell that will remove Europa's barrier.