Thivery Points

Learn to Steal -

NPC: Quick Hand Wang, Water City (57,89)
Monster: Level-4 Cindyfly, Water City Suburb
Reward: Learn stealing skill

Procedure
Go to Water City and find the NPC named Quick Hand Wang (57,89), right click
on him, he will tell you that he will teach you how to steal if you give him
a level-7 Cindyfly.
Go to Water City Suburb, catch a level-4 Cindyfly and raise it to level 7.
Then return to Quick Hand Wang. right click on him, then click on
"No big deal. I'll make it in no time", he will take away your
level-7 Cindyfly and give you 20 points of stealing experience.

You can do this quest repeatedly to accumulate your stealing experience