After making up her mind, Kiyomi no longer felt that weird restlessness in her chest.
She no longer actively looked forward to doing anything and accompanied Nezuko and occasionally watched Tanjiro improve with Kokushibo and Sabito.
And just like this, she watched Tanjiro train for another year.
Tanjiro was able to destroy the boulder easily and getting Urokodaki's permission to attend the final selection.
She herself was also able to be able to break through to the Realm of the See-Through World, and now, she can truly call herself invincible in the world.
Not that anyone necessarily knows that fact except Kokushibo.
After becoming an official demon slayer, Tanjiro went with Kokushibo and Kiyomi to the headquarters to reunite with his family.
Sabito on the other hand went back to doing his Hashira business.
On a few of his missions, Tanjiro met Zenitsu and Insuke, his two best friends on his journey.
And not to forget the love of his life, Kanao Tsuri.
Kiyomi accompanied by Kokushibo, followed Tanjiro around as they watched him in the dark, helping him only when needed.
Along the way, she experienced many fun activities that she, as a work slave in her previous life, never got to experience due to her tight scheduling.
That was fun and all, but the people she met were all weirdos, each one treating her differently, but still respectfully.
The Asakusa Arc - Easily destroyed the arrow and Temari demon. Kiyomi gave Tamayo a vial of her blood for research after Tanjiro left.
Tsuzumi Arc - Tanjiro managed to decapitate the head of the tsuzumi demon in three moves.
Natagumo Mountain Arc - Rui was barely able to incapacitate tanjiro due to him holding Nezuko hostage.
...
"Kughk!"
A heavily wounded Muzan watched in anger and fear as Kiyomi repeatedly stabbed her fingers into his neck, her movements all a vague blur.
All 13 Hashiras watched in amazement while Tanjiro stood by Kokushibo.
He was not expecting his sister to fly out of nowhere and overpower Muzan just as they were about to launch their final attack.
Muzan suddenly shot out several bone spurs in a desperate attempt at trying to get Kiyomi off of him.
Surprisingly enough, that worked.
Kiyomi sprung backward in a backflip and landed perfectly next to Tanjiro.
"Hi~ How've you been Tanjiro? Wait a bit, okay? Nee-san here is going to finish this little problem before you and your little girlfriend get married, kay~?"
A bright vivid blush surfaced on Kanao and Tanjiro's cheeks.
She waved her hands and smiled towards Tanjiro as if the blood on her face was nonexistent before unsheathing the exquisite sword hanging on her waist.
"Breath of the Moon, 17th style~!"
In an instant, she appeared behind Muzan, her sword already back in its sheath.
In the stead of her sword, is an umbrella, purple in color.
A short while after, a chillingly feminine resounding voice spread.
"Dreamwaker's Promise, A Broken Moon."
...
*Blood Explosion*
Muzan directly exploded into a blood mist, and the blood was blown into the air, filling the area with a bloody yet pleasing and refreshing scent.
This is the day, that everyone on the scene would never forget.
...
???: "How do you think she's done?"
??: "Good enough. Give her five years break time, then I'll fulfill your request."
???: "So you admit you've lost the bet?"
??: "...Shinao, you're annoying."
Shinao: "Why thank you! I was hoping you would say that!"
??: "I still won't cancel our engagement though. That's not within my abilities."
Shinao: "Hehe, that's why I asked for my request you know? She has much better potential than me. She'll be able to solve your family."
??: "Whatever."
...
End.