Hashira training

A few days later

Yami was back at the Butterfly mansion and swinging his sword in the garden over and over again. He continued training like his life depended on it, he was obsessed. His constant breathing had evolved into extreme or something because he felt his body getting stronger passively 2x as fast as before!

He wasn't aware of the marks on his face when he was fighting the demon.

He continued training, the crow called him for a special meeting but Yami ignored the crow. It wasn't his, it was Tanjiro's. He didn't listen to Tanjiro's crow, it was too noisy. Another thing, Nezuko was running around in the sun now.

Yami strapped her to his back as a weight and training with her hanging there, much to the others' dismay. Nezuko just hung there as Yami trained, Zenitsu tried to kill him several times but Yami just slapped him away when he started screaming.

A few days later

Yami heard about something called Pillar Training. Shinobu was trying to tell him something this entire time, but Yami ignored her. Then he heard 'training' and perked up. He looked at Tanjiro and nodded at him, Tanjiro said "You get trained by the pillars, all of them, for different aspects. Well not all of them but most of them!"

Yami nodded again and Tanjiro said "Uhhhhh... Stamina, Coordination, Flexibility, Sword skills, Infinity something, and Body training." Yami turned around and walked away towards the gate of the mansion, going to do the training right this minute.

Tanjiro said "Wait! Yami, your weights!" Yami stopped and took off his backpack, the rest happened to be outside at the moment. Yami undid the weights and they fell to the ground with a thud, kicking up a cloud of dust. The girls were stunned and gasped.

Yami put the weights back in the box before taking out heavier ones and clamping them on. He put the box back in his backpack before waving over his shoulder and walking away, leaving footprints in the dirt.

Tanjiro's mouth twitched as he muttered "I didn't mean put heavier ones..." Yami hugged his sword and disappeared.

He arrived at the Pillar Training place and looked at Tengen, who said "IT'S YOU!" Yami nodded and a breeze blew by, Tengen was waiting for an explanation but it never came as Tanjiro wasn't there. Yami blinked at Tengen, who said "Oh well! We'll just train silently!"

Yami trained with Tengen for stamina for 15 days before he left. When he left, Tanjiro came to start the training.

Yami moved on to Muichiro, the Mist Pillar, and trained reflexes and coordination with him, training with wooden swords, while his real sword was strapped to his back. He and Muichiro sparred for 10 tens before Muichiro said "You can go." Yami nodded and left as Tanjiro walked in.

Yami saw Mitsuri again and she stretched him with her strength, Yami was doing full splits and laying his torso flat on the ground while stretching his arms straight up behind him as Mitsuri pulled on his arms.

He didn't speak at all, Mitsuri said "KYAAAAAAAAAAAAAAAAAAAAAAAAA! YOU'RE SO CUUUUUUUUUUUUUTE~!" Yami said "Ah." Mitsuri shouted "KYAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA! <3"

A few days later

Yami left and went to Obanai's house. Obanai didn't say anything and Yami just stared at him with a blank look on his face. Obanai said "That look is annoying." Yami just blinked at him and Obanai attacked him in a room with Demon Slayers tied to posts.

Yami fought Obanai while simultaneously avoiding hitting the tied up Demon Slayers. They fought for 18 days and in the end they finished in a draw. Obanai's attacks bent in strange ways while Yami was fast and had sharp reflexes . It was a good training and after, Yami left to the next place.

He arrived at the Wind Hashira's place. Sanemi slashed wildly at Yami, who used his own wooden sword and fought back against him, slashing and hacking with the wooden sword. The other Demon Slayers there had to back away as their fight got more and more intense, they started speeding up and Yami smashed Sanemi in the jaw with his wooden sword, getting hit in the shoulder.

Yami and Sanemi continued fighting for 7 days non-stop, full throttle, they didn't even eat. Yami and Sanemi were covered in bruises and blood as they continued, eventually, the other Hashira came and pinned them both down, stopping the fight.

Yami got up the next day and left as Tanjiro arrived, going to the final training ground with the Rock Hashira, Gyomei. Gyomei said "Get under the water fall then carry the logs, and then push the rock through town.

Yami hugged his sword and took off his clothes before going under the waterfall, he hugged his sword and didn't say anything.

After 5 minutes

He walked over to Gyomei and tapped his shoulder, saying "This isn't working." Gyomei said "Add logs, young Oni." Yami looked at the logs and then at the trees, he chopped down three trees and tied them together with rope before stacking them on his shoulders and standing under the waterfall, hugging his sword.

He closed his eyes and focused on breathing as the days passed.

He then carried the logs at all times.

8 days passed

Tanjiro and Zenitsu finally showed up.

Yami was in front of a giant boulder, he had 5 trees on his shoulders and his sword on his hip, he put his hands on the rock and let out a breath, Yachiru's smiling face flashed in his mind and he opened his eyes, the 4 tomoe appeared on his cheeks and he started pushing the boulder around. Tanjiro, Zenitsu, and Inosuke were awed before they jumped into training as hard as they could.

Yami pushed the boulder across town and back before Gyomei said "Your training is complete, young Oni." Yami still had the Tomoe on his cheeks. He nodded and packed his stuff up before leaving.

A few days later

Yami was cleaning his scarf and dried it in front of the fire. He smiled to himself and held the warm scarf in his hands, it had discolored patches and stitching everywhere like a patchwork doll. It was extremely ugly but Yami could hear the sweetest song coming from it, an eternal song of happiness and love.

He wrapped the scarf around his neck, fixing it to cover half his face again. He took off his weights and put them away to change them to heavier ones, when he heard an explosion and the song of death and pure evil. The pure evil song was extremely faint and far away but it radiated maliciousness and evil.

He put on heavier weights and put the box in his backpack, he put his backpack on and stuffed his face with candies before shooting off towards the explosion with his scarf fluttering in the wind behind him.

He knew that song.

He had heard it before.

It was Muzan.