"Deliver Can of Grease Gift" is an objective in the quest Learning to Love in Mad Moxxi and the Wedding Day Massacre DLC
Walkthrough[edit]
Head to the South, up the slope. Go to the entrance of Innuendobot's Rectory. Moxxi stands just inside it. Approach her and give her the Can of Grease.
She doesn't like what Innuendobot has to say. She orders you to kill him.