Tsuginohikerori, or the more mainstream name, Kerori which translates into Tomorrow Frog in Japanese.
Kerori is a sensitive frog whose color changes depending upon his mood. Usually a happy, White colored frog, but when he is sad, depressed, or not feeling well, Kerori becomes Green in color. But, as always, Tomorrow is another day, and Kerori wakes up and he is White again.
His friends include:
Tochu is a little Golden Tadpole who loves to be around Kerori, emulates him and someday hopes to grow up to be just like Kerori.
Nijimushi is a Blue Worm that comes around when Kerori is depressed. He always makes Kerori feel better and helps him reset himself and become happy again. Nijimushi then quietly disappears.