Father and Son

My Little Pony Stories Where the Protagonist Is a Princess from the Start

One Soul in Two Bodies, Not Two Souls in One Body!

I want books similar to One Soul, Two Bodies! This Mage's Style Is All Wrong! One mind controlling two bodies, not parallel worlds and not dissociative identity disorder. Please don't recommend anything that's been dropped. Preferably a male-and-female selfcest pairing, and preferably without a System.