He looks similar to his cousin SpongeBob except he has a black mustache, a goatee, round black glasses, orange-and-blue-striped pants, a red tie with olive green dots, and purple and white shoes.
Unlike his cousin, Todd is a very messy person, as his socks are so smelly that Squidward tries to complain about it, but SpongeBob does not let him. Also, when SpongeBob and Patrick come back from Patrick's house, there are smelly socks and empty pizza boxes everywhere.
Todd SquarePants was born to an unknown Mr. and Mrs. SquarePants.
When he was an adult, he stayed with SpongeBob for a few days. He mostly lazed around the house and made nothing but a mess in his cousin's home.
In "Patrick's Staycation", SpongeBob calls himself "Todd" when he welcomes Patrick to Star Rock Inn.