The third season of Isekai Maou to Shoukan Shoujo no Dorei Majutsu.

The second season of Isekai Maou to Shoukan Shoujo no Dorei Majutsu. 
 
Diablo is back! You know…the Demon Lord from another world? Traveling through the woods with Rem and Shera, they encounter a lone girl in tatters, pursued by a powerful Paladin. 
 
You know what that means—Diablo will have to try and hide his lack of social skills once again (and come to her rescue, of course). Let the enchanting adventures continue! 
 
(Source: Funimation)

In the MMORPG Cross Reverie, Takuma Sakamoto is so powerful that he is lauded as the “Demon Lord” by other players. One day, he is summoned to a world outside his own-- but with the same appearance he had in the game! There, he meets two girls who both proclaim themselves to be his Summoner. They perform an Enslavement Ritual to turn him into their Summon... but that’s when Takuma’s passive ability <<Magic Reflection>> activates! Instead, it is the girls who become enslaved! Though Takuma may be the strongest Sorcerer there is, he has no idea how to talk with other people. It is here he makes his choice: to act based on his persona from the game! “Amazing? But of course... I am Diablo, the being known and feared as the Demon Lord!” So begins a tale of adventure with an earth-shakingly powerful Demon Lord (or at least someone who acts like one) taking on another world! 
(Source: J-Novel Club)

Takuma was just another awkward gamer, but a twist of fate sees him summoned to another world–in the body of a demon lord! And no one’s more terrified of the prospect than Takuma himself. He may have power, but he’s in way over his head. So he decides to pretend to be the monster he looks like, and accidentally winds up with a pair of gorgeous slaves: a voluptuous elf and cat girl. It’s not what any of them wanted, but they’ll have to figure out how to work together if they want to survive!
 
(Source: Seven Seas Entertainment)

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