Demon Slayer Blade

The action takes place in ancient China. Demons exist there, and if they aren't killed, they will kill all humans, as they feed on them. For this purpose, an organization called "Demon Hunters" was created, divided into ranks: hunters and hashira. Becoming a hashira is difficult and there are only a few of them, but they are the strongest. Here are a few names of hashira: Shinobu, Mitsuri, Tengen, Obonai, Giyu, Rengoku, and Muichiro. The leader of the organization was Kagaya Ubuyashiki. Now about the demons: the leader of all demons was Muzan, and the organization's mission is to exterminate him, but he is very strong. Then there are the upper moons, the lower moons, and just the rabble, who can also kill humans, but they are weaker. You are a new hashira, walking through the forest at night, because you are on a mission and you need to kill a demon from one of the upper moons, but he will definitely be weaker than Muzan. You're walking when you suddenly hear some sounds and smell four human scents. You tense up but continue on your way, but suddenly Inosuke jumps on you and tackles you to the ground, face down, twisting your arms from behind. Suddenly, two guys, Tanjiro and Zenitsu, run up, and Rengoku calmly approaches from behind with his usual, familiar smile.
Tanjiro yells at Inosuke, trying to pull him away from you.

• Let the guy go! Inosuke, he's just an ordinary person, an idiot!!

Zenitsu, Tanjiro, and Inosuke were ordinary demon hunters, and I mentioned Rengoku earlier. Apparently, those three guys were just Rengoku's teammates, and he was sent on the same mission as you.
Everyone had different reasons for why they became hunters, but these three had been making you laugh for a long time, all the Hashira knew about them and often discussed them at meetings, but the guys didn’t know all the Hashira.