I really enjoyed the part about the monkey. Makes me wonder why he was so disturbed.

I'm a little confused. The page refers to a winged creature resembling SCP-086… but SCP-086 is a tetrahedron that makes sounds that mess with peoples' minds. Is it referring to an old version of SCP-086, is the number just in error, or is it referring to a winged tetrahedron for some reason? Other than this confusion, I rather like it, though.

I like this, but there's one point that seems inconsistent - this:

…the nib is extremely sharp, capable of piercing human skin if pressed even lightly.

seems to conflict with this:

Subject also began tapping SCP-067 on his own body. Subject tapped SCP-067 with increasing force, until ink was being splattered on his fur.

The description sounds like the monkey should be effectively stabbing itself with the pen. I could just be misreading the second statement, since it is somewhat ambiguous, but it does imply the nib is being tapped against the monkey's skin, which should make holes. To be honest, the way I would resolve the conflict would be to remove the first of the two statements, since it really doesn't add to the article or seem to have any purpose or relevance to the SCP's properties.

Does the subject freely relinquish control over their arm, or do they just think they do? Have a test where they threaten a test subject if they don't let go.

Why are the two page images:
1:Not of the same pen
2:Not pale green?

Isn't this a little too useful for an SCP? Not that I mind-I had a similar idea until I found this one.

I would like it if it occasionally made a person write a suicide note or a 'Dear John' letter. It wouldn't even have to force the event to occur.

i really like how this goes from "yeah, ok, pen what knows more than its operator knows, and what draws better than its operator can draw" to "CREEPY MONKEY!"

really makes one wonder what ended up on that paper…

I need to know: what happens if a subject is given the pen and then shownSCP - 012? The consequences would probably be catastrophic, but would probably make for some damn fine creepypasta.

What about repeated tests, use the same subject a few times to see what happens. Does it not work twice? If it works multiple times does it do the same thing with the same subject each time? If not does it get more elaborate, take more control etc.