Dog Man: Lord of the fleas is The fifth book of Dog Man By Dav Pilkey.
Plot - Spoilers Ahead!
Chapter 1: A Visit from Kitty Protective Services
It starts one morning at Dog Man’s House, when Li’L Petey and 80-Hd are working on the Dogmoblie and the roof ramp that opens from the Dog Man House by clapping. After Dog Man gets breakfast out and into the Grand Ballroom, Li'L Petey have transformed the room into a special clubhouse, based around a group called the Supa Buddies. After showing the Flip'O'Rama Mask for 80-HD, they have breakfast. Suddenly though, the doorbell rung and a what to be assumed social worker from the "Kitty Protective Service," shows up ranting about Li'L Petey not going to school. Dog Man and 80-HD have to let Petey go with the social worker, who turns out to be Petey wearing a disguise. He then goes to a bench with Li'L Petey to talk about a story he has had, leading off to the next chapter.
Chapter 2: Petey's Story
(With Many Interruptions)