Here is Dank's last "speech" promising he is too good to run off with money - right before he ran off with squall's money.
Dank Soul Guarantee - Danksurance
The Dank Soul Gurantee is my karma based system of insurance. I acknowledge and respect that karma would play a negative role on me if I were to steal anybodies deposit, thus, offering an incentive to not perform such an action. Dank Bank, as with many other investment opportunities, is largely trust based. I hereby give my word and my soul that I will perform as an honest trader, no exceptions.
Since you've already given your soul away, what do you have left that would convince anyone you have changed?
Your word? Not even your sister takes your word anymore, and she stuck with you even after your parent's didn't.