How does one exactly steal life from a ward?

Are you implying that wards don't have lives? Families? Dreams? Hopes? Ambitions?

#wardlivesmatter

A. Wards die. B. Only things that were alive can die. Ergo, wards have lives.

Sound Logic?

Some of the wards are living/look alive. As such most likely they are all technically alive in some aspect, something similar to the rock golems and all that jazz. Cause I mean, those are just rocks? Right? Yet you suck the life out of them?

See, I always thought wards in this game were plants/flowers thus I never got confused by the whole "Wards can be killed by enemies" sort of thing.