The Nikka Coffey Grain whisky is very different from malt whiskies 

Nose:  you can smell a very different bouquet from those that can be found in Japanese malt whiskies. Actually these are flavors closer to those of the Bourbons.
You can feel the aroma of corn syrup, with some slightly minty fresh notes, followed by melon notes                  Palate:  at the beginning syrupy corn aromas, typical of bourbons, with a background of melon, still slightly minty, and subsequently aromas of mushrooms, chlorophyll and undergrowth.                From:japanese-whisky.com/tasting/nikka-coffey