These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Makai Kingdom
Anticlimax Boss: The optional encounter with Asagi must be unlocked with a level 1000 character and a massive amount of mana. Asagi herself is level 50 and will likely go down with one hit.
Awesome Ego: Zetta is arrogant, hammy, and boastful, which is the reason for a lot his fans.
Crosses the Line Twice: Seedle crosses it three times. He was a well-off villainous samurai who tried to flirt with Salome in life. She didn't reciprocate, so he tried to rape her, only to get a knife to the gut for his troubles. Now fast forward to the near-end of Episode 9, where he wants to kill her off again out of pettiness. Alexander foils the attempt. Then, when Salome is about to be resurrected by Pram and Zetta, Seedle intervenes AGAIN by attacking Pram to disrupt the ceremony and then gives Zetta a Breaking Speech about how he got all his power from Salome. Alexander finally has enough and presumably dispatches Seedle off-screen.
The Updated Re-release has this meeting between Petta and Salome. The only Japanese you need to understand is "Zetta no Musume" - Zetta's daughter. Salome's reactions to this statement are utterly hilarious.
Moral Event Horizon: In the last chapter of the game, Seedle reveals he attempted to rape Salome as a human, and was killed instead. He continuously says that everything would be better if he had done so throughout the last chapter and ending, and tries to kill Pram to prevent Salome's resurrection.
In Japanese, Zetta's self-declared title is Saikyou no Maou, the strongest Demon King. Although variations of the original title exist (Strongest Overlord in the Cosmos), he commonly refers to himself as one Badass (Freakin') Overlord. Guess which one fans preferred?
The title of the game itself was originally called Phantom Kingdom in Japan. It was supposedly renamed in order to remove any confusion about it being related to the previous game, Phantom Brave.