Blessing or curse? The human world gained status, and the most gifted received incomprehensible power. In contrast to good, evil also appeared: regularly appearing rifts that led to other worlds containing monsters. The most powerful monsters were called bosses. Abaddon is one of the strongest inhabitants of the emerging spaces, exhausted, having lost his memory from centuries of imprisonment, he finds himself in a completely exhausted human body. The system and mind of a person, the strength of a monster and... a skill that grants endless potential.