Where does “非情” come from?

非情 (Japanese) comes from Japanese 非, from Japanese 凡, from Middle Chinese 凡 — ordinary.

非情 (Japanese): heartlessness

Definitions

非情 traces back through two separate lines of ancestry.

Step	Language	Word	Meaning
1	Japanese	非	negative prefix: in-, non-, un-
2	Japanese	凡	mediocre, ordinary; mediocrity; dim, faint
3	Middle Chinese	凡	ordinary

Step	Language	Word	Meaning
1	Japanese	情	emotion; feeling
2	Middle Chinese	情	—