How I Became A Demon King

One day after shopping, I suddenly get transported to another world in the middle of a forest with everything that I'm holding. I use the knife I had just bought to defend myself from the strange new creatures.

After A while of wandering around and killing things, I level up a few times, and it becomes easier to kill the monsters. I walk for a few days, eating what's left in the shopping bags. One day, I find a medieval-style village; after looking around, I find a building that a lot of people with armor and swords are going into with an engraving of swords.

It looks like an adventuring guild, and I need to earn money, and all I have is my knife. I ask the lady at the counter for some help picking something, but I can't understand what she says, and I can't understand her.

After a while of trying to understand each other, she directs me to another party and says something to them, and they usher me with them. After adventuring with them for a couple of months, I get enough money for more gear.

After a couple of years of adventuring around with them, I learn the language and culture of the people, as well as that there is an area where monsters rule like humans, along with elves and beast people that share the human continent.

I eventually want to go my own way and explore this new world my way. Soon after leaving the party, I find an unmarked ruin in a mountain. The ruin is a large city inside a hollowed-out mountain, and within the center of the city is a temple with only one thing in the city that I find: A shining silver and blue ring.

When I put the ring on, it stuck on my finger, and a new title applied to my character status: immortal. I ignore it and moved on adventuring for ten more years, but I had stopped aging, and I had acquired a reputation among the people, and they called me the "Young Warrior" in their language.

I got bored of adventuring, doing the same things year after year. I decide to explore The territory of the monsters. As I enter one of the cities, the monsters act like civil humans and look at me but do not attack me. I wander around the monster territories, learning their etiquette and their language. And I soon find myself before a demon general joining their army. The monsters do not wish to attack the humans but find themselves at war with them anyway, along with mutated creatures coming from the east.

The humans have a peaceful life compared to the monsters, who are constantly at war with the mutant waves coming from the east, and they stop them from reaching the human territories.

I climb to the top of the demon army and find myself being praised for my leadership and strength. I find my name spreading far and wide, and every monster knew my name. Soon, the demon king grew old, and I was called to his side, and in his last moments, he crowned me the new ruler of the demons.

I led the demons to immense prosperity and wealth: I came to an agreement with the ruler of the humans to stop attacking. And I advanced their civilization by hundreds of years with my knowledge of Earth combined with magic.

I grew weary of being the demon king as everyone I knew grew old, and new ones took their place. But my legacy is still known throughout the kingdom, and they love me, even without seeing it.

Soon, one of my generals comes to me and tells me that the human kingdom plans to summon heroes and may plan to attack our kingdom. It is the first time I have ever heard of summoning people, so it must mean they are from Earth, too. I am ecstatic at the thought of talking with people of Earth again, and I may be able to find a way back home.

I place a substitute in my place and head off to the cathedral in the human capital. I sneak in at night and hide myself with a few of my stealth skills where the summoning ritual is being prepared. I wake up one day to a bright flash and a group of people wearing clothes from Earth, so I sneak into the crowd and join them on their adventure.