Lug is the assistant of Megumi Hopkins in her treasure hunting adventures.
His first appearance was in MIDARA Volume 1 CH. 1 "Megumi RAIDERS: The Gold of Quetzalcoatl".
Though he's known as Lug in the series, his real name is Noriyasu Kasukabe (春日部 ノリヤス, Kusakabe Noriyasu). This is only mentioned in the character's introduction.