RETURN
Locke, Shadow or even anyone can Steal multiple times by doing the following:
1.Equip Locke or Shadow with Genji Glove, Offering and two Thief Knifes. If the character is anyone else, replace either relic with Merit Award. Extra Thief Knifes can be stolen from Slamdancer in Zozo. Merit Award is a Coliseum item.
2.Just attack! Out of the hits several should be Steal attempts. I managed 7 Steals in one go with Locke once. You could hypothetically have an entire party of thieve... Er, treasure hunters!