Not umeshu but ume wine, produced from the juice of ume "plums" (they're actually apricots, of course, but let's not mess with ingrained mistranslations), made with wine yeasts — and no sake or shochu whatsoever.
It has a lovely dry, slightly sour, fruity-floral fragrance (say that fast three times), which makes it a very fine aperitif.
Kishu is both the name of the wine and the area it's made in — Wakayama (Kishu was the name of the province in olden times).
Where did we drink this? All will be revealed in my column tomorrow...
And it's now up on the Japan Times online...