Take care, with great affection and deep mean

It means to not do anything stupid and stay safe. It is definitely not an acronym for kys.

Something someone says they meant when they get judged for writing KYS (kill your self)

people say this in order to inform someone to "kill them selves" without receiving any consequences from using the harsh term since both phrases are long for "KYS"

All the capital letters spell K.M.S. Meaning kill my self.