>>96286890
I heard Khaine's parents are Slaanesh and Khorne, hence it's got traits common to both. Eldar are grandchildren of the gods, and Slaanesh was born of them, but time is a closed loop in the warp so it's not a problem that he was/will be born out of the people made by his own progeny. The ones' whose future death shall be his own birth, long ago.
It's an atemporal mess like how Samus was born of the death of he who killed him before