The couple were eventually forced to call the police when one of them was left locked in the handcuffs after the other spent a good while trying to find the key to uncuff their better half.

“It was hard not to laugh, especially as my shift was ending. It's among the strangest things I have experienced, but I know that it does happen,” police officer Martin Ferm told Stockholm Direkt.

Police were called to the home in Täby, north of Stockholm, shortly after 5am on Saturday. According to Ferm one of the lovers was rather “proud” while the other was “embarrassed”.

It is not the first time something like this happens, as this story and this one prove.

“Oh yes, we were warned about this at the police academy and it will surely happen again,” said Ferm.

While it was not known what inspired the couple, the sale of sex toys went up in Sweden ahead of the release of 'Fifty Shades Darker' this month. Online shop Sinful said that sales rose by 71 percent in the first half of February.