The Three Sisters of Tenmasou Inn.

Tenmasou is a long-established inn atop a mountain overlooking the sea, in a town called Mitsuse that exists between heaven and earth. The inn is run by Nozomi Tenma, the proprietress. Her younger sister Kanae works as a dolphin trainer. Their mother Keiko is the inn's elder proprietress, who is still resentful of her ex-husband that deserted his wife and family.