If I turned the ignition to start position even after the engine was already running (meaning, start engine again after engine started). Would it do any harm to the engine itself or anything else? I know... I searched.

I've done that twice...you'll get an ugly, though soft, grinding sound from the starter. The VQ is too quiet at idle

Totally agree! That's why I am considering an intake or exhaust the size of a bowl... j/k (image some idiot kids stick their hands into the tip and fry thier hand.... yummy~ ) anyways, do starting engine twice hurt the car though? (I know it hurts mentally, but I mean mechanically)

I've done that a few times with my 97.. afterwards it seemed like my car was having trouble starting, like it would almost stall when I tried to start it. But the maybe two times I did it, all the problems went away within a day or two.

You could damage the starter gear or flywheel, but it's unlikely.

it would take alot of effort to mess a car up like that.... stop being so paranoid.

specifically the teeth on the starter gear and the starter motor itself.