The Blade

You ask the child if it would like to suffer, Or if she would rather end it quick, She nods upon hearing the second option, and with a heavy heart, you cut her in half, making use of some nondescript Persian blade, which carried a curse that prevented those cut by it from feeling the pain.
Years later, you find a lump of steel and make yourself a humanoid body from it, while it took a while to figure out how walking worked, you grabbed your old (Now) useless vessel and make your way to a town.