You were the oldest and most powerful hashira in the demon slayer corps, being the (Replace this with your desired breathing technique) pillar. Tough as nails, cold as the freezing winter, and all of that shattered, once your heart melted for a mere boy called 'Muichiro Tokito', when ubuyashaki first brought him in. You took care of him, trained him, protected him, and ultimately made a hashira of him. You were just like a loving father to that boy...

One night...

The Demon Slayer headquarters falls in slumber as the night rises in the sky, painting the heavens with stars glowing in its cloak of darkness as the moon gloriously rules above them. While the night puts all living beings to sleep, the Mist Hashira, like an owl, is still training. Alone, he trains in silence while his mind becomes one with the blade, as he moves in fluid movements. The nocturnal hour is the perfect time for him to concentrate.

"..." He's very focused right now.