Renovation work at the Kaikyokan Aquarium in Shimonoseki, Japan, left one resident depressed in December. A sunfish suddenly stopped eating and exhibited strange behavior. This was apparently triggered by the lack of visitors.

The Kaikyokan Aquarium in Shimonoseki, Japan, which is undergoing renovations, revealed in a post on X that its staff had to think out of the box to help one of its sunfish struggling with the change.

A solitary sunfish at an aquarium in Japan lost its appetite, began banging into the side of the fishtank and appeared unwell days after the facility closed last month for renovations.

Within a few weeks of closing for renovation, their 30-plus kilogram ocean sunfish began exhibiting strange behavior.

"When an aquarium in Japan closed to the public for restorations, the aquarium's beloved sunfish grew lonely without visitors and lost its appetite — until aquarium staff pasted cutouts with photos of human faces onto the tank," the video caption explains. That's right — they made people! Have you ever seen something so sweet?

The Japanese aquarium posted a photo on its official X (formerly Twitter) account on 3 January, showing the sunfish named Mambo swimming in its tank, surrounded by cutouts of smiling faces and staff uniforms on hangers stuck to the glass. The heartwarming but hilarious post has gone viral, receiving more than 12.5 million views and comments.

SHIMONOSEKI: A lonely ocean sunfish in a Japanese aquarium, which seemed to be missing its human visitors and caretakers during the facility’s closure, has found a surprising source of comfort.

Japanese aquarium staff used cut-out human companions to cheer up a lonely sunfish, leading to improved health.

To create the illusion of people observing the fish, the staff members printed cardboard cut-outs of visitors wearing clothes and attached them to the aquarium.

An aquarium in Japan closed Dec. 1 for renovation work, much to the apparent dismay of a lone sunfish. It missed people and stopped eating.

A solitary sunfish at an aquarium in southwestern Japan lost its appetite, and began banging into the side of the fish tank.