I call my little Crowley, Mr. Smush when he's at the window of his tank asking to come out for missions. My mom's parrot calls him a pretty bird, I'm trying to teach him to say Crowley but so far he just says crow, which has got me starting to call him Crow too now sometimes. I used to called him my little pancake when he was young because he would flatten himself and go in everything. I also call him missions all the time because he loves to come out and do lots of missions around his play area. I also call him my cute little guy at least one a day but don't think that really counts as a nickname.