The story
From Japanese 生菓子(なまがし) (namagashi).
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A type of wagashi which may contain fruit jellies, other gelatines such as kanten, or sweetened bean paste, usually freshly made and much more moist than others, generally containing 30% more water. Full definition →
From Japanese 生菓子(なまがし) (namagashi).
Etymology from Wiktionary, CC BY-SA 4.0.