A male Humboldt penguin who lived at Tobu Zoo in Saitama Prefecture. Grape-kun obtained Internet fame in 2017 for his interactions with a cardboard cutout of Kemono Friends' Hululu the Humboldt Penguin character placed in his enclosure as part of a promotional event, prompting many to consider Grape-kun an old friend of hers, a secret admirer, or as being hopelessly in love with her while being stuck in the third dimension, the latter leading many animanga fans to sympathize with the penguin. He became a sensation, receiving many visitors and a plethora of online fanart depicting him alongside Hululu and even a visit from Hululu's anime voice actress, Chikuta Ikuko.
He was distinguishable from other Humboldt penguins at the Tobu Zoo by the purple armband on his left flipper.
According to zoo staff, Grape used to have a wife called Midori (distinguished from her green flipper band, midori being the Japanese word for that color), but at some point she abandoned Grape-kun and found a new lover— a rather exceptional occurrence in a species that usually forms lifelong pair bonds, and a source of suggestion as to why Grape-kun grew so attached to the Hululu cutout.
Grape-kun passed away from a sudden illness on October 12, 2017, at the age of 21. A temporary message board was set up near his enclosure for visitors to leave parting words, and many additionally left gifts such as artwork and flowers.
