He wears a white fedora hat and a purple suit. He has pink eyes like his two daughters, a five o'clock shadow, and dark hair with some gray. He also has a scar that runs down the side of his cheek.
Although he looks intimidating, Big Daddy does have a soft side, especially for his daughter, Wanda. He also sleeps with a pink horse-head plushy named "Mr. Nay-Nay," a reference to a famous scene from The Godfather. Despite this though, he's strictly business and is easily annoyed by Timmy and Cosmo's antics. He also has a tendency to use the threat of making people who oppose him "disappear".
A running gag is that he has all the appearance of a Mafia boss and is constantly making reference's to his garbage business which could be a parody of "The Godfather". He has two daughters, Wanda Fairywinkle-Cosma and Blonda Fairywinkle. His son-in-law is Cosmo Cosma, who fears him, and even Wanda is afraid when he gets mad. Even though he may be tough, he has a pink, horse head pillow named "Mr. Nay-Nay" when he sleeps and cares for Wanda more than anything. He holds affection from Mama Cosma, and the reason is they have the same thing in common, they do not like who their children are married to.
Big Daddy first appears in Talkin' Trash, where he helps Timmy Turner and his fairies get rid of the Magic Trash that was building up in his home from all his wishing. Upon his appearance into Timmy's room, Timmy who was being lazy ordered Big Daddy to clean the trash up. Big Daddy refused and after seeing that Wanda married Cosmo, who he believes is a terrible son-in-law, he tries to make Wanda go back with him. Jorgen tries to stop this, but Big Daddy throws a huge amount of garbage on Jorgen and the latter is forced to make Big Daddy a deputy that allows him to take away a godparent if they are helping a child in need.
Realizing his parents will be killed by the Stinky Magic, Timmy takes away Big Daddy's tools. Big Daddy was not happy about being touched or his stuff being taken and tries to threaten Timmy, but Timmy defiantly says that Big Daddy makes people disappear when people touch him and declares that if Big Daddy will not help him, he'll save his parents himself. Timmy then fought off the Stinky Magic and nearly got killed by it, but Big Daddy saves Timmy and gets rid of the Stinky Magic for him as he saw how much Timmy loved his parents (but he warns Timmy not to stand up to him again if his parents are in jeopardy again). He then allows her daughter to be with Cosmo while also threatening Cosmo a bit before disappearing.
He later reappears in "Big Wanda", where he disappears and Wanda is left to run the family business. At the end of the episode, it is revealed that he was spending the day at Mama Cosma's house, and there was even a hint to them liking each other, but this was never touched upon again as this was Big Daddy's last appearance in the series. Big Daddy, along with his other daughter Blonda, were strangely absent for the birth of Poof, and neither have appeared in the series since Season 5.
While it's obvious that Wanda and her father are very close and she obviously loves her father, at times, she has trouble standing up to her father, as shown in Talkin' Trash. After he disappeared in Big Wanda and saw that Wanda had taken over the family garbage business, he was shown to be happy about that, and he was okay with some of the changes she had made (but made some changes of his own).
Big Daddy didn't like Timmy initially, mainly because of his laziness and lack of respect for him and his daughter, but he gains respect for Timmy after he stood up to Big Daddy and risked his life to save his parents.
It's unknown what kind of relationship Big Daddy has with other daughter, Blonda, as he seems closer to Wanda, although Blonda did seem (somewhat) concerned for her father after hearing about his disappearance, but she had planned on using the grief of that to motivate her in her soap operarole as Nurse Blonda.
Cosmo's mom had kidnapped Big Daddy in Big Wanda, although the two were surprisingly attracted to each other (much to the disgust of Cosmo, Wanda and Timmy), as the one thing they had in common was that neither of them like who their children married. Even though Big Daddy doesn't like that Cosmo's his son-in-law, he seems more willing to put up with Cosmo than Mama Cosma's willing to put up with Wanda as her daughter-in-law. This is shown by Mama Cosma's attempts to kill Wanda in the past, something Big Daddy has (presumably) never attempted on Cosmo.