I'm not a :)

[plasmid]

Roaming eyes will float about

Finger doomed to poke them out

Button nose that touches heart

Let them never fall apart

Gaping mouth with toothless bite

Swallow not the soul I smite

Best if sinner lets me lay

Righteous lord will lead the way

[DudleyDude]

a cigar cutter

I'm at a bit of a loss as to how to respond to this one without it being a major clue. But whether this is within the realm of acceptability or not has a great deal to do with the specific nature of the device you have in mind.

I was thinking of these but I think TL's guess is much more likely and certainly fits the riddle better.

[plasmid]

Right you are, TL. For your first answer, I hadn't even realized that it had that inherent religious connection to fit the last two lines.

was the dextros- / sinistros- referring to right and left handedness. Scissors are perhaps the most common devices engineered for a specific paw latitude.