As the series' own interpretation of the devil, he is an appropriately prideful and sinister being feared for his adept use of trickery and deception. By taking advantage of his victims' latent greed, the Devil is shown to use gambling at his casino as a method by which to encourage his victims into making increasingly reckless, Faustian bets, eventually culminating in the forfeiture of their soul to him upon their loss.

Both a liar and a cheat, the Devil naturally has no problem with going back on his promises so long as it benefits him, turning Cuphead and Mugman into his slaves for handing over the soul contracts in spite of promising to spare them if they do. Even his own minions he shows very little sympathy for, declaring his right-hand man, King Dice, a "a good-for-nothing lackey" after he has been beaten.The Devil's main trait is that he is incredibly prideful of himself, believing he'll always win in the end as he brushes King Dice off when the latter tries to warn him about the brothers becoming stronger.