How Not to Summon a Demon Lord Ω

異世界魔王と召喚少女の奴隷魔術Ω (Isekai Maou to Shoukan Shoujo no Dorei Majutsu Ω)

6.4(1)

OtakuDen

6.7(213,958)

MAL Score

Ranked #6754

Popularity #568

Action
Comedy
Ecchi
Fantasy
Romance
Harem
Isekai

Episodes: 10
Duration: 24 min per ep
Aired: Apr 9, 2021 to Jun 11, 2021
Status: Finished Airing

Synopsis

Diablo returns to the world once again—only now he’s mistaken for a divine being. After a chance meeting with High Priest Lumachina Weselia, Diablo and his companions set out with the enigmatic cleric on a mission to purge corruption from within the Church. Convinced that Diablo is “God,” Lumachina’s faith draws him into protecting her as she pursues her first objective: locating the head paladin, the upright Batutta.

Alongside Rem and Shera, Diablo’s party expands to include the grasswalker Horn and the Magmatic Maid, Rose. As Lumachina’s request grows more complicated, Diablo is left to navigate her expectations—and the question of whether a Demon Lord from another world can convincingly fill a god’s role.

Otaku Consensus

How Not to Summon a Demon Lord Ω is a leaner, faster sequel whose best qualities are Satoshi Kuwabara’s brisk direction, Kazuyuki Fudeyasu’s uncomplicated series structure, and action scenes that still give an overpowered lead room to use tactics. The Church-centered material and expanded party give the season more forward motion than a pure harem comedy, but the dominant criticism remains the same: its ecchi content is frequent, explicit, and divisive enough to push away viewers who otherwise enjoy isekai power fantasies.

Why You Should Watch

Watch Ω if you want a compact isekai power fantasy that delivers confidence, embarrassment, fanservice, and spell-slinging without asking for a 24-episode commitment. It scratches part of the same itch as Overlord, in that the lead’s absurd strength is filtered through a performed persona, but it leans much closer to harem comedy and ecchi spectacle than world-conquest drama. The appeal is in the contrast: Diablo can dominate a fight, yet the show keeps returning to social awkwardness, party chemistry, and the ridiculous pressure of being treated like something greater than he is. If you like tactical magical combat, fantasy-party banter, and shameless genre excess, and you are not looking for a restrained or prestige-style isekai, this sequel knows exactly what lane it is in.

Key Characters

D
Diablo(VA: Masaaki Mizunaka)
Diablo remains interesting because his overwhelming in-game power is paired with a painfully constructed Demon Lord persona, turning even routine social exchanges into performance anxiety.
R
Rem(VA: Azumi Waki)
Rem is the party’s grounded counterweight, giving the harem setup a sharper emotional center than its fanservice-heavy packaging suggests.
S
Shera(VA: Yu Serizawa)
Shera’s appeal is her openhearted chaos, which keeps the trio’s chemistry playful rather than purely possessive.
L
Lumachina Weselia(VA: Miku Ito)
Lumachina gives Ω its most distinct sequel flavor by bringing absolute religious conviction into a cast built around role-play, misunderstanding, and genre self-awareness.

What Makes It Stand Out

1
Ω is only 10 episodes, airing from April 9 to June 11, 2021, which makes it a tighter sequel cour than the standard 12- or 13-episode fantasy season. That shorter structure lines up with the recurring positive reception around its acceptable pacing and quick movement between comedy, action, and new party dynamics.
2
The season is credited to Okuruto Noboru and Tezuka Productions, giving Ω a co-production identity rather than a single-studio billing. For database-minded viewers, that production credit is one of the cleanest ways to distinguish this sequel’s making from a generic continuation entry.
3
The action is frequently discussed less as raw spectacle and more as an overpowered protagonist still applying tactics. That matters because Diablo’s strength could flatten tension, but the better fights lean on spell choice, positioning, and situational problem-solving.
4
The ecchi is not a side garnish: AniList tags the season with Nudity at 72% and Psychosexual at 20%, matching the review pattern that calls its explicit scenes both central to the appeal and the biggest barrier to entry. Viewers sensitive to fanservice should treat that as a content warning, not a minor genre label.
5
Ω expands the party beyond the three best-known leads with Lumachina, Horn, and Rose, shifting the sequel from a closed trio dynamic toward a more crowded fantasy-party structure. That expansion is one reason positive commentary singles out the season’s likable cast chemistry and broader range of locales.

Fun Facts & Trivia

Fun fact 1: The anime continues material from Yukiya Murasaki’s original story, with Takahiro Tsurusaki credited for the original character designs that define the franchise’s fantasy-harem look.
Fun fact 2: Kazuyuki Fudeyasu handled series composition, a key credit for a sequel whose reception often points to pacing as one of its stronger qualities.
Fun fact 3: Shizue Kaneko served as character designer, with Rina Morita on sub-character design and Tetsuya Kawaishi on prop design, showing how the production split visual responsibilities beyond the main cast models.
Fun fact 4: Despite a moderate MAL score of 6.68 and AniList score of 66/100, Ω has broad visibility: the research data lists 213,958 MAL votes, MAL popularity at #568, and 2,023 AniList favourites.
Fun fact 5: The sequel’s Greek omega symbol is part of its official title, distinguishing How Not to Summon a Demon Lord Ω from the first TV season in Japanese and English database listings.