By rights, Mundungus Fletcher should have had nothing to do with the Dursley family, but after being frightened by the Dementors, he actually wanted to stay with Harry so he could "protect Harry."
Mrs. Figg did not go inside with them. She told Mundungus Fletcher and Harry to be careful, then returned to her own house.
The two of them struggled to carry the unconscious Dudley into the house. Harry felt as though they were hauling a pig.
When they brought Dudley into the living room, the Dursleys were watching television.
"Diddy!" Seeing a scruffy, balding man carry Dudley into the living room on his back, Petunia Dursley screamed and sprang off the sofa. "Vernon! Vernon!"
"What have you done?!" Vernon Dursley heaved himself off the sofa and roared at Mundungus Fletcher, breathing heavily. "Let go of my son!"
"Calm down, calm down," Mundungus Fletcher said, laying Dudley on the carpet. "He's fine, just a bit... sleepy."
Vernon charged forward with clenched fists, shoved Mundungus Fletcher aside, and gathered Dudley into his arms. "Dudley, son, what's wrong?"
After shaking him a few times and getting no response, Vernon glared viciously at Harry. "Boy, what are you playing at? What happened to him? What did you do to him?"
"We didn't do anything!" Harry stood his ground. After all, he really had done nothing wrong. "I saved him! Do you understand?"
"You used... used one of those tricks your kind does on him, didn't you?" Vernon was beside himself with rage.
Just then, an owl flew into the house, breaking the tension. It dropped a letter at Harry's feet. Harry ignored Vernon's murderous glare for the moment and opened it.
Inside was an expulsion notice from the Improper Use of Magic Office. Harry's ears seemed to fill with a buzzing noise,