Warnings: Death, Violence, Kidnapping, Mentions of Religious Concepts, Toxic Mindsets.
A.N. - In honour of All Hallows' Eve, I present the Devil himself.
Platonic:
To have a good time with the Devil, one must pull the lever while he pushes the button on causing worldwide destruction. He expects all his evil deeds to be praised and treated as spectacles of skill and charisma, not horrors to be criticised and bad-mouthed.
Snubbing him for his actions, which include scorching anyone who acts too friendly for his liking, will get dozens of demons turned to ash. Rejection makes his temper shorter and shorter until he is eating souls in plain view of others to frighten them into keeping their distance.
No one is safe from his flames when the Devil decides that he has had enough and explodes in a fit of rage. If they are not incinerated in the blast, all the people who have gotten in his way have their souls ripped from their bodies and cast into Hell.
Henchman gets an earful as the Devil rants about how useless and unreasonable everyone is. The Devil asks a rhetorical question about whether he should skip the niceties and go straight to the abduction stage, and Henchman, forever the supportive fellow, tells him to do what makes him happy.
Belonging to the land of the living means that many a deal is offered by the Devil to join him in Hell. Most revolve around landing a seat next to his throne and becoming a high-level demon in exchange for serving Hell in perpetuity, but there are a few that involve staying in the Inkwell Isles and running his casino.
Rejecting one of his deals leads to catastrophes everywhere. The Devil stews over this rebuff and orders his unholy legion of demons to pillage the world, an order that he agrees to rescind if his deal is then accepted. However, there is no guarantee that he will not continue the order later out of spite.
All of Hell hears his roars when there has been an argument between the Devil and the one who he forbade everyone from addressing. Demons know better than to get involved, but the souls of the living are not always so keen to turn a blind eye. Cuphead and Mugman have intervened and lured the Devil away more often than not.
Romantic:
The Devil would like a partner in crime more than anything else, someone who revels in the chaos as he does and laughs with him when famines sweep through the land. Anyone who stymies this fun together is incinerated on the spot.
Engaging in relations with someone besides him is strictly forbidden. This rule is in effect before he even makes his intentions clear, and if it is broken, the Devil will covet this illicit relationship and seek to make the other person one of the damned.
As soon as death comes and the soul leaves the body, the Devil appears in a ring of fire and snatches it. He makes an accommodating afterlife in Hell by his standards, although he views the situation as a belated victory and demands to know why none of his generous deals was accepted.
If Stickler appears with Hell's rulebook in his hand and deems the situation an unlawful seizure of a soul, the Devil rages against his words and prepares to incinerate him right then and there. No one is allowed to question this particular action lest they face the business end of his pitchfork.
Managing to escape back to the Inkwell Isles as a ghost is a herculean task that will require help. Henchman and King Dice are far too loyal to the Devil to consider helping, so the assistance comes in the form of Cuphead and Mugman's shenanigans.
One day, the Devil is preoccupied with hunting the pair or brooding in his chambers over the fact that they escaped his clutches yet again. The elevator to and from the land of the living is left unattended, and using it has never been easier.
Once the Devil realises what has happened, entire forests are washed away by waves of fire. Search parties are comprised of the nastiest fiends from Hell's bowels, surveillance portals are opened from one end of the Inkwell Isles to the other, and the Devil himself rises from the inferno to terrorize civilians into giving up information.