"My friend is staying in a hotel in Belgium. They've offered her the option of renting a fish for the night, in case she's lonely," Cook wrote.
The Hotel Charleroi Airport near Brusssels has offered the fish rental service to guests for several years.
"We started a few years ago. The idea was to surprise our guests, as we always try to do," hotel manager David Dillen told The Independent. "It's brilliant to see how people react to it. They smile, they take pictures to put on social media. We rent a few fish per week."
Dillen said he and his brother initially came up with the idea to keep guests entertained during check-in, but they became so popular he decided to expand the service.
"I was having a beer with my cousin and we saw some people waiting to check in," he told The Telegraph. "The queue was quite long so I decided to go out and buy some fish [as entertainment]."
Some people have criticized the policy for being unfair to the animals, but Dillen assured the fish are well cared for.
"I can also tell you that we take very good care of our fish; they have been with us for over four years now, so if they were not taken care of they would have died a long time ago," he said. "They also have a big fish-tank in the housekeeping department, with a shelter, oxygen and plants. When we think it's necessary, we put them there for a few days."