I would like him to sound like he did in Lupin the 3rd part 2s dub. However if you can't do that please feel free to do your own thing.

In Monkey Punch's original manga, Lupin is cocky, quite crude, and for the most part remorseless. He is very much the ladies' man, often using them for his own gains, but is not beyond forcing himself upon women who resist him. This is in stark contrast to his better-known anime self, who despite being a skilled thief, comes off as a goofball and will go to great lengths to right injustice, who also shows a chivalrous streak that compels him to help those less fortunate than he. Furthermore, Lupin often takes it upon himself and his gang to stop criminals engaged in more violent crimes and leave them for Zenigata to arrest. In the anime, while he fancies himself a Cassanova, his actual success with women is erratic, appearing to fluctuate with the writer.

 It seems Lupin loves to steal more than actually having the treasure he sought. Lupin relishes more in the challenge of stealing and, as long as he succeeds in the heist, is usually not that upset when he ends up empty-handed; there have been times he has lost the object or intentionally thrown it away. There have also been times when Lupin stole an object only to give it to someone else, such as if it rightfully belonged to them or they needed it more than he did.