Yamato nadeshiko (やまとなでしこ or 大和撫子) is a Japanese term meaning the "personification of an idealized Japanese woman", or "the epitome of pure, feminine beauty".
You can read more here: https://en.wikipedia.org/wiki/Yamato_nadeshiko
Oh that's nice of you to add in the LN illustrations.
Others should do this too! It's interesting to see differences or similarities between the sources.