He was once twice the size of a normal cat, weighing almost two stone.
But Mr Pickles is now showing off his lean new shape, after staff at an Aberdeenshire rehoming centre put him on a strict diet.
The stray cat was rescued from the streets of Balmedie last July, and tipped the scales at one stone, 9lbs.
Staff at the Scottish SPCA’s Drumoak rescue and rehoming centre immediately put him on a tough diet and exercise regime – even taking him for walks in a dog harness and a lead.
Now the three-year-old moggy is at much more healthy weight of just over a stone.
Assistant manager Debbie Innes said: “We’re all so proud of Mr Pickles for reaching his goal weight.
“He has been spending a lot of time out of the cattery and in our staff room to help him get a bit more exercise.
“His slimming was always going to be very gradual as losing too much weight too quickly could have caused serious health problems.”
Staff had originally planned to rehome Mr Pickles after he reached his target weight, but they have become so attached to him over the last year they have decided to keep him as the centre cat.
Ms Innes added: “Mr Pickles has been at the centre for over a year now and has become something of a local celebrity. His fan club often pop in just to see him and get a cuddle.
“Children adore Mr Pickles and he really is one of the friendliest cats we’ve ever met.
“We’ve decided that he’ll stay with us as the centre cat as he is so at home here.
“Everyone has totally fallen in love with Mr Pickles so we’re all really glad he’s sticking around.”
And although Mr Pickles’s story has had a happy ending, Ms Innes warned others to take heed of the dangers of overfeeding their pets.
“Sadly, cats diagnosed as being clinically obese can have a shorter life expectancy,” she said.
“They also have an increased risk of developing diabetes, liver problems, breathing difficulties and joint stress.
“It’s extremely important owners keep their cats at a healthy weight. Anyone concerned that their pet may be overweight should consult their vet.”