The final battle had finally begun. Goku, after clashing with Muzan Kibutsuji alongside Gyomei Himejima, was falling in the Infinity Castle.
"Fine, bring it on!" he exclaimed to himself, turning his body face down and spriting forward, accelerating the fall. I hope my eyepatch doesn't fall...
He sneaked through buildings while falling, slicing some demons' heads. Eventually, he fell alongside Giyuu, landing beside the Water Hashira in a crouched position and with his fist on the floor.
"I'm ready, Giyuu," he said.
"Fine. Let's go," said Giyuu, starting to walk.
"Okay!" said Goku, following him. But then, he stopped. "Wait, Giyuu. I have... Something to do."
"Huh? What do you mean?" said Giyuu.
"It's about Shinobu-chan," said Goku. "She... She is about to die, I know it."
"Really? How do you know?" asked Giyuu.
"Because while I was retiring to my room after our chat back then, I heard her conversation with Kanao-chan," Goku explained. "Her body is full of poison, and she's aiming to be eaten by the demon who killed her sister, so she can defeat him from the inside."
"Really? We gotta go save her, then!" said Giyuu.
"No. Only me," said Goku. "I'll reach you later, you can keep walking."
"Why only you?" asked Giyuu.
"Because... I've been in love with Shinobu-chan since the day we met on Mount Natagumo," Goku confessed. "Please, understand it. If I save her, maybe she'll finally understand how much I care about her..."
"...Fine. I understand" Just don't get killed in the process," said Giyuu, turning and continuing to walk forward.
"Understood..." said Goku. Then, the boy turned and started searching for Shinobu. Shinobu-chan, hold on... I won't allow you to die!
Far away, Gyomei and Muichiro were walking together.
"There are a huge number of demons, don't you think?" Gyomei said. "It seems like they've been boosted to the power of a Lower Moon. They're trying to weaken us..."
"What about Oyakata-sama?" asked Muichiro.
"He reached death before us," said Gyomei. "It was a dignified death. He knew he hadn't much more time to live, so he decided to use himself as bait."
"I see... When I was knocked off by a demon, I was on the border between life and death," said Muichiro. "Oyakata-sama stayed with me all the time. He did the same with the other members of the Corps... He acted like a father..."
"Yeah, I know..." muttered Gyomei.
Meanwhile, Sanemi was sitting alone. A demon approached, but he quickly beheaded it.
"They keep coming... Bring it on, lees... I'll kill you all!" he exclaimed, getting up. From his eyes, tears descended.
Elsewhere, Inosuke was running alone, while cutting a pair of demons' heads. I ended up in this place suddenly, and there are demons everywhere! Perfect to test my training!
Genya was confused, walking cautiously. What's this place? Is this a demon base? Aniki... Be careful, Aniki!
Elsewhere, Shinobu was walking alone, as she noticed a door. I smell blood...
Then, she opened the door and found a demon, but not an ordinary one. The demon turned after feeling Shinobu's presence.
"Oh, a girl! You look young and tasty! I must thank Nakime later!" he said. Looking at him, Shinobu noticed the kanji of 'Upper Two' on the demon's pupils. That demon was Douma, Upper Rank Two. Suddenly, Shinobu had a flashback.
The girl remembered when her sister, Kanae, was killed back then. The Insect Hashira was holding her sister in her arms, in tears.
"Shinobu, please, leave the Demon Slayer Corps... I want you to live and get old..." said Kanae.
"No! There's no way! I have to avenge you!" said Shinobu. "Tell me, what kind of demon defeated you?"
"He had a red spot on his head..." explained Kanae. "This demon always smiles and sneers and talks calmly and gently..."
Then, Shinobu returned to the present with her mind and noticed Douma had the same characteristic as the demon who killed Kanae.
"Hey, nice to meet you!" said the Upper Moon. "My name's Douma. Nice evening, huh?"
It's him... realized Shinobu. Then, among the corpses of the women Douma had eaten, one of them was still alive.
"Please... Help me!" she said, crying.
"Can't you see I'm still talking?" said Douma. Quickly, he hit the girl with his fan. Fortunately, Shinobu was quick enough to grab the girl and drag her to safety.
"Are you okay?" she asked.
"Oh, you're fast! Are you a Hashira?" asked Douma. Suddenly, Douma's hits felt, and the girl was sliced into three parts. "Don't worry, you can leave her corpse there, I'll properly eat her later!"
Shinobu remembered another detail her sister had told her before dying.
"That demon... fights with two sharp fans."
Shinobu turned to face Douma, and he had exactly two sharp fans.
"I'm the Founder of the Paradise of Eternal Hope," said Douma. "My goal is to make all my followers happy, including me.
That's the demon who killed my sister... realized Shinobu. "Make them happy? Ridiculous! She wasn't enjoying it and begged for help!"
"And I helped her, didn't I? She's not suffering anymore, as you can see," said Douma. "Everyone fears death. That's why I eat them, so they can live inside me forever. I firmly support the feelings of believers..."
"You're crazy," said Shinobu. "You disgust me."
"Huh? We never met before, but you're really rough," said Douma. "Oh, I see... You must've lived a very traumatic experience... Tell me, I'll listen."
"Traumatic experience? You killed my sister! Don't you recognize this haori?" shouted Shinobu, furious.
"Mh? Oh! The girl who used Flower Breathing?" said Douma. "She was very sweet and cute. I didn't finish eating her because the sun rose. I remember. That's a shame, I really wanted to eat her."
Before Douma could finish speaking, Shinobu stabbed his eye with her sword. "Insect Breathing: Dance of the Bee Sting."
"What a fantastic attack! I didn't manage to stop it with the hand..." said Douma. "Blood Demon Art: Frozen Lotus!"
Chapter 51 - End