Shaggy bought a pet that turned out to be a talking dog. The dog's name is Scooby Doo. I don't know how it happened but Shaggy noticed it when Scooby was just a puppy. Shaggy would talk to Scooby like any normal owner would talk to their pet. One day while playing with Scooby, Shaggy told the puppy he loved him and Scooby responded
"I rove rou roo rhaggy"
Shaggy was not scared but amazed. He didn't think this a something to profit on but something to value. Pretty soon Scooby Doo would start communicating with Shaggy like he was Shaggy's child.
We are just going to skip ahead about 10 years into the future. By this time quite a few people knew about the special Scooby Doo. What I mean by "quite a few" is majority of the town Shaggy lived in. There were so many opinions about Scooby Doo. Some people thought Scooby was a demonic dog. Some thought Scooby was a god. Shaggy saw Scooby as his best friend and that little puppy that said I love you back.
"Rets ray Rhaggy." Scooby Doo requested.
"You want to play Scooby?" Shaggy asked.
"Res" Scooby responded.
Shaggy ran to grab a dog toy for Scooby to play with and went for the door. When Shaggy opened the door and saw a crowd of people wanting autographs and pictures with the talking dog. This was when Shaggy realized that he and Scooby had to leave town and start a new life.
The very next day Shaggy started packing up to relocate. Shaggy was scared that something bad would happen to Scooby if they stuck around his current town. The people would treat Scooby like a celebrity instead of a dog. Shaggy wants a normal life for Scooby but this wouldn't be possible in their current residence.