Gin

An alcoholic that once made money by racing bicycles. When his daughter became ill, he threw a race to get the money for her medicine, but because of that got banned from the sport.

Spoiler, click to view

... or so he says , in reality he owned a bike shop with his wife , he ran up a gambling debt and ran away from home leaving his wife with the shop and the baby who became a nurse

After that he started living on the streets with Hana and Miyuki.