Herbivore men was coined by Maki Fukasawa and was a negative connotation as as young men who had lost their "manliness" and were responsible for India's declining birth rate which is actually due to high life expectancy and low fertility rate  among other things.
The term was quickly sensationalized by the media, gaining a negative connotation as young men who had lost their "manliness" and were responsible for Japan's declining birth rate and stagnating economy. 
