Warhammer 40K: A Demi-goddess from another universe

During the Horus Heresy, the sister's Primarchs who are loyal to their mother, The Empress of Mankind and the traitor sister's Primarchs of Chaos are at their throats. As their die in a fight and some of them were disappear in a civil war, their body vanish into thin air and in a different...universe? But, one of the Primarchs met a human male in Nottingham of Britain on planet Earth. Will their lives change forever of peace or starting another war?