I take the "Reborn as an Orc" idea and add to it. 

An orc grew up reluntant to hurt anyone because of reoccuring nightmares. They figure out after one big noggin BOOP! that the nightmares were shattered traumatic memories from their previous reincarnation, a human victim to a murder mystery in a 1950 alternative universe.
They do not know what to do with this, but is very upset and confused.

And yeah, I agree with some of the earlier posts. Kaiju Mama sounds great.