Kumano Umeshu

Literally, Ume means "Japanese apricot" or simply a plum, and shu is another way of pronunciation of SAKE (酒), then Umeshu is normally called as Plum Wine, though it is a kind of liqueur to be accurate.
Kumano Umeshu has the fine balance of gentle sweetness and noble sourness. You may try this as neat, on-the-rock, with water/soda/hot water.
Umeshu is also used for confectionery cooking.