THE HEROIC TALE OF AN UPSTART EXPLORER IN A WORLD FULL OF DUNGEONS 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.cc fastest updating comic site. The Summary is

Modern Japan where dungeons occur. Hayato Amahara, a 16-year-old junior high school graduate, is a poor explorer who sips the slime he has hunted and lives in a ragged house in the accident property. However, when he met a mysterious beauty, Hexa, his life turned around! It was a "weapon creation" that can create weapons! Unique beautiful girls gather around him!?