As video game franchise Pokemon is about to celebrate its 20th anniversary on 27 February, one fan in particular will be delighted more than others. Lisa Courtney holds the Guinness World Record for the largest collection of Pokemon memorabilia, amassing more than 16,000 items related to the monster battling franchise.

The 27-year-old, who lives with her mother in Welwyn Garden City in Hertfordshire, first started collecting the toys at the age of nine after seeing Pikachu in a Nintendo magazine. Since then, she has become obsessed with catching them all.

Ive got an awful lot of different Pokemon memorabilia. Ive got your traditional plush toys, electronic devices, games, DVDS. But Ive even got the rarities like Pokemon toilet paper, she told Barcroft TV.

Theres just something about collecting Pokemon that brings a smile to my face. Theres just a feeling of accomplishment when you finally get that last piece.

Courtneys mother Sharon said: Lisas collection has definitely taken over the house. Its taken over the bedrooms, its taken over downstairs, its taken over the garage, its taken over the shed, the hallway, the landing. It would be nice if I could say I had a bit of the house to myself but no it has definitely taken over.

Sharon even moved out of her master bedroom to accommodate her daughters burgeoning collection.

When Lisas collection started to get big I decided to move down to the small room. It didnt bother me at all. She was happy, I was happy, but it was a little bit of a mistake because [the collection] built more and more, she added.

Lisa has held the record as the worlds biggest Pokemon fan since 2009, when Guinness first awarded her for the worlds largest collection of memorabilia at 12,113 items. Seven years on, her collection shows no signs of stopping. She added: I will always collect Pokemon. I will never stop, theres always something new to get.