"We appreciate all your donations, but less 'Fifty Shades' and more '60s and '70s vinyl would be good," the charity wrote in social media post showing stacks of its unsold back stock

Oxfam employee Phil Broadhurst told the Mirror the store has become a "retirement home" for the novels.

"There are a lot of people obsessed by 'Fifty Shades of Grey,'" Broadhurst told the Mirror. "We get people bringing in new copies coming in all the time. Enough is enough."

Published in 2011, the novel tells the story of the dark, sexual relationship between college student Anastasia Steele and wealthy businessman Christian Grey. The book quickly gained popularity. More than 125 million copies have sold worldwide.

In 2015, the novel was adapted into a film starring Dakota Johnson and Jamie Dornan.