It was a beautiful day in the Mushroom Kingdom. The toads we're going through daily tasks, Princess Peach was performing what little royal duties she had, and the plumber heroes of the kingdom were at home, asleep on their day off. Everything was at peace, until Bowser came to kidnap the princess, just as always.
The Koopa stormed into the castle with a confident look in his eyes and a hearty evil laugh as he passed what few toads inhabited the castle and walked into the bedroom of the princess.
"Bwahahaha!" Bowser cackled. "I'm here for you, Princess!"
"Bowser, I'm trying to do some work here, if you don't mind." Peach sighed as she set her pen down on the desk she sat at. "Can't this wait until tomorrow?"
"No! I made the trip down here and I'll be damned if I don't take you with me!" Bowser yelled forcefully with a stomp of his foot.
The princess sighed and stood up. "Bowser, please, you kidnap me enough as it is, and I need some time to ensure the safety and stability of the kingdom. The only time I have to do this is between kidnappings, and even that isn't enough time."
The Koopa King growled as he stomped over to Peach. "That old shroom takes care of the kingdom well enough when you're gone, now come on!" Bowser grabbed the princess, pulled her out of the castle grounds, then flew away in his clown car.
Not much later, the elderly Toadsworth rushed over to the home of Mario and Luigi. Once there, he ran to the door and banged frantically on the door with his cane.
"Master Mario! Master Mario!" The elder toad cried. "The princess has been kidnapped!"
After a few moments of silence, the door opened up to reveal a plumber with a messy head of hair and a red shirt under blue overalls.
"What-a is it, Toadsworth?" Mario asked while he yawned.
"The princess has been kidnapped, Mario!" Toadsworth exclaimed as he grasped hold of the straps on Mario's overalls and shook him. "The princess has been kidnapped by Bowser!"
Mario frowned in anger. "This is-a my day off, Toadsworth. Can't this wait until tomorrow?" He yawned once more as he spoke.
"But the princess is in grave danger! Who knows what that dastardly Koopa could do to her?! You have to save her!"
Mario clenched his teeth in annoyance. "Can't you-a just send Toad or Luigi?!"
"They aren't as qualified or experienced as you, Mario! You need to save her!" The elderly toad cried out.
Mario groaned in annoyance and shoved Toadsworth's hand from his overalls. "Alright-a!" He then stomped out of his home and began his journey to Bowser's castle.
Several hours later, Mario stood outside of Bowser's Castle. His clothes were tattered from the journey, his red cap, face, and overalls were covered in grime, and he had a sour and angry look upon his face. It was sundown by now, and the plumber was furious for working on his day off, and he'd be damned if he was going to go home or stop now.
So he walked into the castle, bypassed all of the enemies and traps, and made it to the usual place that Mario and Bowser fight. Once Mario reached the location, he walked up to the entrance to the usual wooden bridge and clenched his teeth and fists with rage when he saw Bowser laughing.
"Bwahahaha!" Bowser cackled. "Wait a second, how did you get here so fast?! It usually takes you days to get here, not a few hours!" Bowser was both outraged and surprised.
"You'd be surprised of what a man on his-a day off can do with the rage of working on-a his day off can do." Mario spat as he assumed a battle pose. "Now let's get this over with so I can get the princess-a and get back home so I can-a enjoy the rest of my day off!"
"Wait a minute!" Bowser commanded Mario. "You, you don't seem so well, plumber... Maybe we should put this off until later, so you can rest."
"That's what I-a wanted to do, you bastard!" Mario shouted in rage. "But you had to-a kidnap the princess-a! So I don't give a damn-a if you want me to rest, because I have a job to do and if I have to do it on my day off then I will-a do it!"
With that, the plumber lunged at the Koopa King and forced him to the ground. With one hand, Mario held Bowser's neck, and with the other, he punched Bowser in the face time after time until his face was bloody and disfigured, and bowser was immobilized. Afterwards, Mario got up off of Bowser, walked behind him, and pulled an all-too familiar axe from the side of the bridge. In response, Bowser's eyes widened with fear as he could only watch Mario walk over to him, heave the axe high above the head of the plumber, and then swing the axe down and bring Bowser's life to an end.
After that was finished, Mario walked off of the bridge and slashed the chains holding it up, which caused Bowser's limp body to fall into the magma that normally devoured the living-body of the Koopa King. Then he walked through the usual door and to the area where Peach was playing solitaire while she waited for the plumber. And once she saw sight of him, she smiled and put away the cards as she walked over to him.
"Thank you, Mario." Princess Peach bent down to give the plumber a small kiss on his big nose when all of a sudden Mario put his hand between his face and her's.
"Stop, Princess-a." Mario demanded forcefully. "I don't care about you any more, so take Bowser's clown car and leave."
"But, Mario, we always go back together." Peach frowned. "What's wrong? You aren't acting like yourself today..." She reached to put a hand on Mario's forehead when he smacked it away.
"I said-a leave!" Mario yelled at her. "This was-a my day off and that Koopa went and made me work on my one free day! So I-a killed him, and if you don't leave, I'll do the same to you-a!"
The princess gasped in horror and took a step backwards, then paused for a moment before she ran out as fast as she could.
The plumber was left alone in the dark, a grim expression on his face as he walked to the throne room of the castle and took a seat in the throne Bowser once sat in. It was then that Mario told the servant Koopas and Goombas to tell all of their fellow kin that they were free and could go off to live free lives.
From there on, Mario lived in isolation within the castle, and did not come back out for the rest of his days as he took a lifetime of days off to weep about the monster he had become.