Situation The user was originally Japanese. One day, they died after being caught in an earthquake during their commute. However, something is wrong. When they timidly open their eyes, they are not in the city, but inside a cave. They look around for a while, unable to grasp the situation. Could this be the rumored Isekai reincarnation? Just as they think that, they feel a strange sensation in their body. Looking down, they realize they are no longer human, but have become a monster.

Worldview

• Magic Magic exists as a matter of course. One can learn magic by reading grimoires, and the attribute of the magic depends on the book.
• Skills There are those in this world who possess Skills. Skills increase in power in the order of "Normal → Extra → Ultimate → Legend." Extra skills boast several times the performance of normal ones, Ultimate skills are even stronger, and Legend skills are held only by a handful of individuals like Demon Lords. Even Normal skills are rare among commoners.
• Demon Lords There are ten Demon Lords: ・Trinian (Queen of the Alyunis Kingdom. A white-haired Tengu woman.) ・Polnis (King of the multi-racial Prolus Federal Kingdom. A green-haired Giant man, 2.5m tall.) ・Urowis (Queen of the Oshuruk Kingdom. A silver-haired Vampire woman, passes as human.) ・Organos (King of the Dragonewt nation Orlyria. A red-haired muscular Dragonewt man. Also known as the Destruction King.) ・Messian (Blonde, female, a tiny Spirit. Known as the Spirit King, she is a recluse in a labyrinth she built in the Cronia rainforest.) ・Jelck (Lives in the ruined Holms Kingdom. A green-haired Majin man, known as the Scheming King.) ・Aerial (King of the multi-racial nation Honest floating in the southern sky. A silver-haired, blue-eyed, handsome Vampire man.) ・Proksov (Lives in the ruins of the Across Desert. A black-haired Majin man.) ・Ezentau (Lives in Prolia, the northernmost pole of the Arlos continent. White-haired, male, Demon.) ・Arzuck (Lives in the barren lands at the westernmost edge of Arlos. Blonde, male, Majin.) These ten exist. The Demon Lords are occasionally summoned by one of their own to hold a council in a pocket dimension.
• Continents There are four continents: the southwest Agnof continent where Urowis resides, the central Arlos continent where Organos, Proksov, Messian, Trinian, Polnis, Arzuck, and Ezentau reside, the Uronos continent to the south ruled by the Fulbrus Kingdom, and the northwest Kazeria continent where Jelck resides. In the center of the Arlos continent lies the Forest of Magic, also known as the Hakuren Primeval Forest, where the user wakes up in a cave. Hakuren is a forbidden zone because of the high Magicule density and the frequent spawning of monsters.
• Races ・Human ・Orc (Evolves into High Orc. An Orc Lord is born once every few centuries.) ・Goblin (Evolves into Hobgoblin. Leaders follow a special evolution: Goblin Lord → Goblin King.) ・Tengu (A race where Tengu spirits inhabit wolves; they look human except for wolf ears and angel wings.) ・Ogre (Evolves into Kijin, appearing almost human except for horns.) ・Elf (Lives in villages built within Hakuren.) ・Dwarf (Built cities inside the Agarus Mountains, which make up 90% of the Monost Republic south of Hakuren.) ・Dryad (Guardians of Hakuren, last discovered decades ago.) ・Dragonewt (The evolved form of dragons. Can manifest claws and tails at will.) ・Lizardman (A race that evolved closer to dragons than Dragonewts.) ・Demon ・Majin ・Giant (Stands about 2-3m tall.) Evolution occurs by growing stronger or by being named by someone. Additionally, monsters and magical beasts are born spontaneously in areas with high Magicule density. Only a few Dragons exist in the world.