Colby Krause is the life coach Marge hired to help Homer get a more successful job. He is not a very good one, which he even admits. Marge spent all their savings on hiring him. He gave Homer confidence to land the private jet that had gone out of control.
Behind the Laughter
The character's appearance is based on his voice actor, Stephen Colbert.
Colbert expressed his delight at the fact that the character resembled him and was named Colby.