Nezumi

There are still many mysterious creatures in this universe that we don't know about. On a distant planet, one mysterious species has come into existence. They are known as "Bananyas." What sort of planet do the Bananyas come from, and what sort of life do they lead? And what if they began to dream about coming to Earth someday? Source: crunchyroll

"Bananya" are neither cats nor bananas, but cats hidden in bananas. They come out and play when people are not watching.

The story centers on a crocodile living a normal life, unaware that he is due to die in 100 days. The crocodile spends ordinary days with his animal companions. Source: ANN