Within a Hollow Heart - Chapter 34: Volume 1, : "Ripples in the Veil"

Once an unsung slave; Yur’s existence was defined by blood, pain, and chains. That was until he stumbled into Zulmasharr, the realm of demons.In the depths of despair and agony, a near-death encounter unsealed the terrifying truth of his existence; he is no mere mortal. A cursed hybrid of human and demon; Yur’s survival was only possible through the bloody rebirth of his Ashkavaal bloodline and the awakening of his sinister cultivation system, Zul.With Zul, Yur can rear demons for rituals, harvest their power, and dominate the chaotic world around him. But freedom comes at a cost. As the incognizant successor to an ancient being, his every step is burdened by the weight of a destiny he never asked for. Yur craves only one thing: to stay free, unbound by demons and men. Yet his growing power and severed bloodline ignite the fascination of forces that would see him enslaved or slaughtered.Yur must steer through a world of demons where trust is a fault, survival is animus, and his very existence is a blemish. Blood will pour, flames will revolt, and demons... they kneel or die. But in the end, is freedom attainable for the bearer of a bloodline forged from blood and ash?Will Yur vanquish his fate or will it condemn him?

My crew? Yeah... it's a little special.First Division: Night Raid from the Akame Ga Kill.Second Division: The Akatsuki, led by Pain, from the Naruto world.Third Division: The Seven Deadly Sins.Naval Headquarters:“Everyone, be on high alert. That man... he's coming.”Four Emperors:“Sh*t, who the hell provoked him this time?!”“Someone get ready to apologize. I’ll go in person if I have to...”The Dragon Hunting Pirates — a name that makes the entire world tremble!

This is a story of a little man who walks forward silently, in awe, and strives to chase his dream.

- Description from novelbuddy

One-eyed Wolf Lecan is a skilled adventurer who has conquered many dungeons all over the world. He had been going solo for a long time, but in the last three years, he’s had a partner. That partner jumps into the black hole together with Lecan, and both go their separate ways as they fall into another world. Dungeons and magical beasts also exist in that world. After learning the native language, Lecan goes on a journey. Meeting a good teacher, Lecan studies medicine making and magic under that teacher, and begins his dungeon explorations for real.