Keroppi is a frog who loves adventure, and his bubbly personality makes him popular around Donut Pond. He has a brother called Koroppi and a sister called Pikki. Keroppi is a fantastic swimmer and singer (but not at the same time!). He is a hard worker and has a hobby of playing with arcade machines. Keroppi's name comes from "KeroKero", ("ケロケロ") a Japanese onomatopoeia for the noise a frog makes.