If No is chosen, The Devil accuses the brothers of leeching off of him just like the other debtors did, and will immediately attack them.
After The Devil has been defeated, he unwillingly surrenders to the brothers. Cuphead states that he and Mugman will accept his surrender, but they weren't finished yet. The brothers then proceed to burn all of the soul contracts, releasing everyone they had previously fought from servitude to The Devil, and set off for home, with Cuphead being excited to tell everyone the good news. Subsequently telling the Inkwell Isle residents that they are free of their debts and won't be bothered again, the residents throw a celebration as thanks, alongside Elder Kettle who is proud of the two.
If Yes is chosen, The Devil proclaims that the brothers now belong to him and that they're going to have "a hell of a time" in Inkwell Hell. The scene then switches to Cuphead and Mugman being transformed into more demonic beings with evil grins on their faces while The Devil smiles in triumph. Once the scene ends, the credits will roll, but the music will instead play a more somber tune.
The debtors are not seen in this ending, but it is implied that they will be severely punished by The Devil for not giving their souls on time.