To be loved

Harry Potter at age seventy ,looking eighteen, Master of Death itself, was bored ,broken and out of his mind as a stray deaging spell Hit him spare the chest, turning him physicly as mentaly into a four year old. Death, seeing a Chance to save Its masters Sanity and heart in that, took him with him ,into a World unbeknowst to himself, as his much worse Sister ruled there over the Dead.
Twisting Harrys powers to fit the New realm, Death became his past self once more, realizing, that this whole ordeal may also accure ,to save him as well.