Rozer

Hyunwoo is, for all intents and purposes, a loser. Grade A. Freshman year of college was horrible and his sophomore year's shaping up to be more of the same. But, things take a turn for the weird when he saves the life of an old snake-oil peddler on the way home. As thanks for his good deed, the old man offers Hyunwoo a special potion guaranteed to make all his dreams come true. Add in an apartment building made up of hot chicks, including his college crush, and Hyunwoo's about to have his hands full.

The protagonist is sucked in to a weird whirlpool in a river and somehow ends up in a island in another world with native elves that wear leaf clothes, have the knowledge of an new born, and have sex like rabbits. That also have a body as weak as butter. He decides to become the king of the place and rule with an iron fist and teach the naive elves cruelty, evil and watch as they kill each other.