Dialogue before the quest start
Our partnership has been quite fruitful lately, it's great - and I want to trust you more. After all, reliable people are valuable. It's time I let you in on a delicate operation I'm running at the resort. However, first, I would like you to prove your loyalty to me, bring me a necklace made from the ears of your enemies. He-he, just kidding about the ears. But I am serious about loyalty - If you want in on this operation, you'll need to prove your loyalty to me, and not necessarily with blood. You know exactly what I mean.
Dialogue after completing the quest
As I thought, you are a man of business. Now I know that I can count on you not only in assignments but also in financial help, he-he.