An Observer from Hell (Chainsaw Man x Male Y/N)

A suspected betrayal and the birth of a new Hero.

It has been more than three months since Denji and Y/n had been paired up by the debt collector to kill Devils together, and they were able to reduce Denji's debt to less than 30 million yen. The last one they defeated was the Tomato Devil.

He wasn't much of a threat. It was just that he was a pain in the ass because of his ability to revive using his seeds which needed to be burnt or destroyed immediately after he created them.

Denji was happy that his debt had significantly lowered during those past months. Y/N, on the other hand, was a lot more tired than usual since he killed lots of devils as fast as he could while also upgrading and refining his skills, making it extremely hard for certain devils to even hurt him, even without what he gained from this contract that he had made with that devil.

It's not like he wasn't using them because it wasn't necessary; it was more that he was too scared of the outcome of using those. Denji was sleeping on the newly bought couch he paid with the money he gained and saved from killing devils.

Sometimes he invited the blond boy to eat at his home, which he accepted whenever asked. Then, something stopped the silence within the apartment.

Knock, Knock

"Denji, Y/N, we've got another devil, time to work!" the old man said, still knocking on the door, waiting for both of them to come out. The black-haired boy's eyes widen from shock, "Already?" he thought, staring down at his bandaged hand.

"Denji coughed blood... yeah, everything checks out... god, I don't know if I'm prepared for this..." he continued thinking. However, his train of thought was cut short by Denji, that was now waving his hand in front of Y/N's face.

"Hey, Y/N, you're okay in the head right now?" he asked, waving to get his attention. Y/N sighed, stood up, took his axe, and approached the door. "Yeah, just spaced out a bit. Let's beat some devil's ass!" the younger teen said, opening the entrance to the old Yakuza.

They walked out of the apartment and to a car which led them to an abandoned and decrepit factory. The old man exited the vehicle, then Y/N exited the car, followed by Denji. Then, they entered the building. It stank horribly, worse than Denji when they both met.

He tightly gripped the axe in his hand while looking around. It could happen any second now, so he had to prepare himself. "There's a devil out here?" Denji asked the silent debt collector, who continued walking forward instead of answering.

Y/N noticed that it stank even worse the more he followed the Yakuza. Denji looked around him, not seeing anything around, "Can't see one; guess it's hiding somewhere." the blond mumbled, looking at one of his two friends, Pochita.

Then the old man stopped, prompting Y/N and Denji to stop moving. While the blond boy let his guard down, the other teen had his guard higher than ever. "Denji boy, young Y/N, you both have our thanks." the debt collector said, looking at the darkness before him. "Ah yeah..." Denji mumbled, with his guard still down.

"Denji, you're obedient like a dog, happy to work for cheap treats like a dog too." "Y/N, you're a machine, killing devils stupidly fast, making us gain more money than lots of our members." The old man continued, making Y/N nervous and Denji confused about the meaning of what he was saying.