Cops caught Jordan Heppell, Davy's cousin, with meow meow - mephedrone, and they also found horse tranquilliser ketamine and marijuana in his car.
Heppell from Crowthorne, Berks, showed how he was selling the drugs and why.
"I was probably selling 20 to 30 grams at 20 pounds a go to about 20 people every week. I only did it to support my weed habit," said Heppell.
He was arrested for intent to supply class B and C drugs and was released on police bail until Sep 2010.
"I think she'll be shocked," said Heppell of 24-year-old Davy's reaction.