Doflamingo tried multiple times to invite the famous underground boss Sir Crocodile to join his Empire, but he refused every time Doflamingo was asking or did send others to ask.

This lead to an obsession by Doflamingo to not let go until he would have convinced him one way or the other. He also seems to have grown other interests in him.

One day he ordered his crew to kidnap Sir Crocodile. With success.