Sloth King is a Manga/Manhwa/Manhua in english language, Webtoon series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

Treasure, power, authority- just like all kings, the Sloth King has it all. Kaz, a lazy young man, has been chosen as one of the candidates for the Sloth King. He and the other candidates had to compete in a major tournament to determine who would become the next Sloth King.