Tanjiro opened his eyes to find himself in an odd garden type area. His box containing his little sister Nezuko was seated right next to him which he was very grateful for. It seemed to be the backyard of a mansion. Butterflies were flapping around but no one at the moment was in sight. Then almost like a butterfly herself a woman came into view gliding down. She wore a purple demon slayer outfit, a coat that resembled butterfly wings and her hair was black with purple at the ends.
 "Who are you" said Tanjiro
 The woman turned around and gave him a soft smile.
 "I'm a hashira, the names Shinobu and I've been put in charge of your punishment for harboring a demon" said Shinobu
 Tanjiro's eyes widened and he went to speak but Shinobu cut him off.
 "We are aware of the situation but it's to dangerous, although I don't feel like losing another demon slayer member so I won't kill you...but since I'm in charge I'm allowed to do anything I want with you and her" said Shinobu
 Shinobu giggled and then walked over to Tanjiro and the box picked them both up and brought them inside to a darker room.
 "I had everyone leave today so I could have my fun so you can scream but no one will help or even hear you" said Shinobu
 Another innocent giggle came from her but he got bad vibes. Shinobu set the box and Tanjiro down. Then Shinobu smiled at Tanjiro
 "Before I get to your sister let me make you tired and not move to much" said Shinobu
 With his legs tied he couldn't move away as Shinobu pulled his pants down and then removed his underwear.
 "Its cute...I'll work with it though" said Shinobu
 Tanjiro tried to protest but then she touched his dick. She played with it until it got erect. Shinobu was finally satisfied with its size and wrapped her hand around it. She put her head over it and a glob of spit seeped from her mouth and fell onto his cock. Shinobu used her hand and drenched his dick and started to give him a hand job. Tanjiro twitched at the wonderful feeling and Shinobu just smiled at him. She ramped it up and bent down. Shinobu's lips touched the tip and then her mouth slid over the cock and she started to blow him. The wet slurping and rubbing filled the room. Shinobu didn't have any trouble deep throating it and used all her nifty tricks on him.
 "I'm about...to cum" said Tanjiro
 Tanjiro came inside of Shinobu's mouth and filled it with his cum. Shinobu stopped sucking and took her mouth off getting all the cum off his dick.
*gulp*
Shinobu swallowed the cum with a single gulp and smiled.
 "You must be feeling tired now...your cum wasnt enough to satisfy my belly so I'll go ahead and take the next big thing" said Shinobu
 Tanjiro tried moving but he felt super sluggish and combining that with the rope he couldn't move at all. Shinobu unbuttoned her demon slayer outfit letting her large tits flop out and exposed her entire front side. She smirked at Tanjiro and then turned to the box then walked over to it. Shinobu opened it and found the demon sister known as Nezuko.
 "Leave her alone" said Tanjiro
 "I've already made the preparations to do this so shut that cute mouth of yours and watch" said Shinobu
 Shinobu used a drug that keeps demons sleeping for a while so Nezuko would be out for a while. Shinobu lifted the sleeping demon up and then licked her lips. Tanjiro could only sit and watch as Shinobu opened her mouth and then wrapped her lips around his sister's head. Shinobu slowly went down Nezuko's face consuming it whole until it touched the back of her throat.
*gulp...gulp*
Shinobu's throat expanded with Nezuko's entire head. The shape of her mouth gag could also be seen but for Tanjiro he could only see Shinobu's backside. Shinobu's lips expanded over the slim shoulders of the young demon girl and she pushed her in further. The shoulders went in easily and Nezuko's flat chest slid across her tongue with ease.
*gulp*
Next up was her slim belly which Shinobu reached down and slightly pushed against Nezuko's butt forcing her in faster. Her entire midsection was swallowed and Shinobu stopped at her hips. Nezuko's lower half hung out of Shinobu's mouth and her head was being pushed into Shinobu's stomach. Shinobu used her legs and turned to look at Tanjiro. It was a horrific sight to see half his sister hanging out of the jaws of a fellow demon slayer.
*gulp*
Nezuko's butt was pushed into the maw and swallowed. Her belly started to get bigger with each gulp and Shinobu decided to tease Tanjiro by putting her hands on the ground and crawl towards him while swallowing.
*gulp...gulp*
Nezuko's legs were almost gone and with each crawl towards Tanjiro her belly swayed a bit. Shinobu was almost in Tanjiro's face as Nezuko's feet slid into her mouth. It almost looked like Shinobu was going to kiss Tanjiro. Her mouth closed and she lifted her head up to show him her neck.
*gulp*
Tanjiro watched the final bulge of his sister go down Shinobu's gullet and watched the large gut hang all the way down.
 "Spit her out...give her back" said Tanjiro
 "Nope...I'm going to leave this room and digest her in peace...I'll let her brown remains out right in front of you later" said Shinobu with a grin.
 Tanjiro had no strength to struggle as Shinobu easily stood up. Her breasts and belly exposed to him. Tanjiro could see the vague shape of his unconscious sister bulging from Shinobu's stomach and tears welled in his eyes. Shinobu waved to him and turned. She walked to the door, her belly swaying back and forth to the sides sloshing a small pool of acid around inside. He called out one last time as she shut the door sealing him in darkness and silence. Shinobu looked down at her gut and lightly poked at it. She poked and poked until the bulge moved a little. Shinobu hates demons more than anything and this girl in her belly was a demon. She didn't care if the demon had not eaten anyone yet a demon is a demon. Shinobu wanted her to suffer the pain of being melted alive and listen to the painful screams.
 "Finally you're awake..how about you struggle for the next hour or so and let me enjoy this" said Shinobu
 Shinobu went into her private quarters and stripped down to nothing. Her curvy body was a one many men craved in the corp but she only teased them.
*bwarrp*
Shinobu belched and an acid soaked sandal came out of her mouth slapped the ground. Shinobu rubbed her now moving belly and laid on top of her bed. Sweat ran down the sides as digestion kicked into high gear. Digesting demons took lots of work and was one of the only ways to kill them. Inside her stomach Nezuko had fully awakened and was trying to find out what to do. The tight walls were squeezing and massaging her body rubbing corrosive acid all over her. Her pink kimono was starting to rip and melt away. The acid stung her skin badly and was melting it away.
*mmmpphhh*
Finally the screams of pain came and Shinobu smiled. She couldn't help but reach and touch herself a little bit.
 "That's it little demon scream for your life...all the humans your kind takes away screamed the same way...melt away like they do in other demons" said Shinobu
 Nezuko tried scratching the walls but they were thick and all the wetness made her claws slide off. Nezuko's clothes washed away and the acid assaulted her naked body. She pushed at the walls and her muffled screams kept coming. Her thoughts went to Tanjiro and she wanted him to save her. The mouth guard came out and she spoke.
 "Tanjiro..help" muttered Nezuko
 *glop..blurgle...churn*
The painful screams were replaced with groans and gurgles. Nezuko lost feeling in her body and found it odd she was dying in such a way. She thought only the sun and having her head cut off by a certain sword was it. But it seems being digested does the trick as well. The acid bubbles and Nezuko was melting away. Her skin melted off her body and she reached up as the acid reached her neck. It was futile though and her eyes rolled back and she sank into the acid.
*crunch...slosh*
Shinobu watched a hand imprint go down and couldn't contain herself and squirted all over her bed.
 "The only good demon is a dead one" said Shinobu
 Shinobu grabbed her belly and squeezed, breaking Nezuko's bones and helping her belly melt her skin. Nezuko's mangled body was melted down with ease and turned into a nutritious slush that Shinobu would absorb.
*groaaoonnn*
The wet sweaty belly already started to go down and Shinobu absorbed the demon girl. Nezuko became fat and nutrients leaving only a pudgy belly left on Shinobu.
 "I guess I'll show his sister off" said Shinobu
 Shinobu got up and didn't bother getting dressed with only her hair thing still on. Shinobu went to the room Tanjiro is in and opened the door. Light flashed in his eyes and he saw Shinobu. Her belly was way smaller with no sign of Nezuko in it. Her breasts were double the size from last time and her thighs were jiggling with each step.
 "Mmm I can feel her reach my colon...looks like it's time to see your dear little sister" said Shinobu
 The sexy nude hashira turned her fat ass towards him and spread her cheeks out. Her puckering anus fully visible now moved a little and Tanjiro felt his heart drop as a brown log started to come out. No sign of his sister's old form, just a brown smelly log of shit. Shinobu looked back at him to see his horrified face and smiled. The long thick turd dropped from her ass and piled in front of Tanjiro. Shinobu grunted and a second log with some bones in it fell from her ass.
*plop..thud*
Tanjiro cried seeing that his little sister was nothing more then shit now. Shinobu moaned a little, feeling the soft butt loaf coming out. Nezuko's skull dropped and Tanjiro noticed only the top half was there. He could see his sisters fangs and eye sockets with shit covering them. Then a log came out and he noticed the lower jaw of his sister was mixed with it. Shinobu stood over the large pile and let a golden stream of piss out, making the shit shine. Shinobu giggled and looked at Tanjiro in the eyes.
 "I think I'll keep you here instead for a while until I fully break that mind of yours...bye bye" said Shinobu
 Shinobu left and sealed Tanjiro in the room with the poop pile. The smell of the scat smelt awful and made him pass out.