And despite her tiny dog costing her a small fortune and most of her monthly income, Butler wouldn't change her diva ways for the world.
Lilly now has over 17,000 followers on Instagram and receives hundreds of messages from strangers who are in awe of her style.
Butler, who works as a dog groomer in Royal Tunbridge Wells, Kent, said: "Lilly loves wearing dresses, she has over 1000 of them and each cost around £100.
"She has so many clothes and accessories such as hats to match every dress and around 50 different leads and collars, that she has her own wardrobe.
"Most of Lilly's clothes are handmade so you can't get her style on the high street.
"If I don't put her in an outfit she tends to drag her box of clothes out as if to say, 'come on put a dress on me.'
"She's such a little character and she loves posing for the camera.
"That's why I set up her Instagram page to document her little life.
"Lilly definitely has more clothes than me but I don't mind, I wouldn't have it any other way.
"I tend to wear jeans and a jumper or T-shirt but Lilly always goes for the glamorous look, I think it suits her the most."
Butler, who lives with her parents, first adopted Lilly back in 2015 and it didn't take long before the dog was wearing her first dress.
She added: "At first I was buying Lilly a new dress every week, it was costing me a small fortune but seeing her looking so adorable made it impossible to stop.
"But now I have calmed the spending down a bit and tend to buy her something new every few weeks instead.