Training Muzan into a Well-Behaved Puppy

On an ordinary day, while you were watching Demon Slayer, you were bound to the Villain Redemption System.

System: [The first world is Demon Slayer, and your target is the scum of the demons, Muzan Kibutsuji. Host, show off your extremely popular personality and go all out to win him over and redeem this evil villain!]

With acting skills off the charts and a nature that might be just as rotten as Muzan's, you raised an eyebrow. Me, redeem Muzan? Seriously?

You looked at Muzan's practically perfect face, and an underhanded thought surfaced at the most inopportune moment.

Redemption? Well, it's not like I can't do it~

If you train the Demon King into a well-behaved little dog who does good deeds, does that count as redeeming the villain?

You curled your lips into a half-smile. It should count, right~

For Muzan Kibutsuji, meeting you was both the most regrettable and the luckiest thing that had ever happened to him.

Regrettable, because he would lose the dignity of being the Demon King because of you.

Lucky, because thanks to you, he would become a perfect creature.

The utterly contradictory feelings made him try to escape from your side again and again, only to return to you of his own accord time after time.

Then the cowardly yet cruel Demon King would receive a twisted yet obsessive love from you.

One day, after you had once again chopped Muzan into thousands of pieces, he lay on the ground and writhed resentfully. Twisted, I can accept, but how exactly do you love me? You're nicer to that bunch of useless underlings than you are to me!

You: Only a good dog who listens can earn its owner's favor~ Isn't that common sense?

Muzan: ...How many times have I told you? I'm the Demon King, not a dog! I'll kill you, see if I don't!

You: Hmm?

Looks like the little dog still hasn't learned its lesson.

So even if Muzan-chan gets down on his knees and begs this time, you won't go easy on him~

Your dog-training routine was going so smoothly that it surprised you, until one day your arrogant little dog, having underestimated his opponent, was bullied by another target of a different System.

Just as Muzan was about to be sliced into sashimi by the King of Curses, Sukuna, a pair of slender, delicate hands caught his severed head.

"Not just anyone gets to bully my little dog."

You lowered your expression, your eyes like a bottomless pool of icy water. "Have you figured out how you want to die, bastard?"

If the protagonist had to be compared to something, they'd be the Blue Spider Lily turned into a spirit, but unfortunately the scummy boss can't beat them, hahaha!

In the early part, he tries to take the protagonist by force and gets beaten up. In the middle, he both loves and hates them. By the end, he's been trained into a little dog who is fierce to everyone else but meek and obedient around them.

Since the protagonist's dog-training methods are pretty bloody, the scummy boss never manages to commit most of the evils he does in the original story.

Also, the author threw the timeline out the window!! Don't scrutinize it too closely!!

Theme: Train the dog, train the dog, train the dog!!!