I Rely on My Harem to Conquer the World is a Manga/Manhwa/Manhua in english language, Action 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

Young Li Haoran tragically died after being ruthlessly betrayed by his teammates in a battle against demonic beasts. However, when he opens his eyes again, he finds himself reborn as the Blood Demon King in a tribe full of succubi. On top of that, he has acquired a special system that allows him to grow stronger simply by building a harem. This time, he will seize the opportunity, forge himself into a true demon, and lead his harem to conquer the world!