Nationality French Lupin II is the son of the legendary Arsène Lupin, who took up his father's mantle as a notorious thief. Sometime during his later career, he sired a son who was third in line to be named Lupin, allegedly with his wife Tomoe. According to Tomoe, this was a marriage Arsene didn't approve of.

Spoiler

Not much is known about the thief or his actual whereabouts but according to various sources he is dead.