Rainbow Dash hadn’t even made it out the door before Derpy was already fully alert once again, and back to coloring. Curious about what the gray pegasis was drawing, and with nothing else to do, I walk over and lay down beside her, making sure that I’m brushing next to her; a reaction to that would be useful for one of my other ‘plan/theories’.

When I do, she doesn’t hesitate to lean into me, in a way that even I -- with my ‘ample supply of extensive diction’ -- could only describe as...instinct.

...almost too useful.

Suddenly, Derpy jumps, startled, and dives to cover her drawing. Appaaaarently, she was drawing something that she didn’t want me to see, which, fortunately -- well, fortunate in a way that only my cryptic perception of reality could comprehend -- I hadn’t seen what she was drawing.

Perhaps it simply wasn’t finished yet. This is Derpy’s drawing, remember?

“I take it you don’t want me to see what you’re drawing.” I point out with a soft smile.

Derpy doesn’t speak for several seconds, then replies “No...not...yet.”

The tone in her voice seemed...mixed between sad and serious. She was laying her head on her hooves, her body covering her drawing. Her tongue wasn’t hanging playfully out of her mouth, and her eyes were looking ahead of her...both eyes.

This is the side of Derpy that few ponies ever get to see. In fact, those close to her don’t even refer to this side of the gray pegasis as ‘Derpy’.

This...is Ditzy Doo.

“Well, if it comforts you, I didn’t get a chance to see it. Your startled jump startled me, too. Next thing I knew you were already where you are now -- covering it.” That’s not a lie, either; she really had caught me off guard.

Ditzy seemed to perk up a little from my remark. She began to readjust herself to a sitting position once again, clearly taking great care to keep the drawing hidden. Pressing the drawing against her chest with a hoof, she turns around and faces me, and looks at me...again, with both eyes -- which she is easily capable of doing...it’s...just not her default setting, per say.

Then again...the same is true of ‘Ditzy Doo’. Even though ‘Ditzy Doo’ is her real name, it isn’t her real personality. That honor goes to ‘Derpy Hooves’.

“What...about earlier?”, she says, now clenching the drawing against her chest with her other hoof as well.

I shook my head. “I was only able to see that you were drawing something; I still have no idea what you were drawing, though.”

I can see her start to smile -- well, sort of.

I start to stand back up. With a smile of my own -- well, my half-smile -- I say “And if I’m correct...the longer we keep talking about this, the longer I’m going to have to wait before I do get to see it.” I softly laugh before adding “And I believe I’ve already given away too much of my patience to be able to last too much longer.”

The result:

Instant Derpy.

As spontaneously as Pinkie Pie’s “Party Cannon” (I haven’t seen it myself, but I have been told -- scratch that -- warned a lot about it.), Derpy was back to being...well, Derpy: tongue playfully hanging out, and her eyes living up to the name.

“Let me know when it’s finished, okay?”

Derpy nodded as only Derpy can, and I left the room to allow her to finish...well...her drawing.

_______________________________________________________________________________

Author's note: In this story, the gray pegasis' birth name is Ditzy Doo, but she's more commonly referred to as "Derpy Hooves", which is attributed to her also more common playful personality, whereas when she's more serious, she's instead referred by her birth name.

In case that run-on made little sense, here's a visual:

Ditzy Doo:

~birth name

~uncommon

~characterized by:

~normal eyes

~more serious mood

~tongue not hanging out

~comparable to:

~Pinkamena

Derpy Hooves:

~nickname

~much more common

~characterized by:

~'derpy' eyes

~much more random mood

~tongue playfully hanging out

~comparable to:

~Pinkie Pie

I hope that helped in some way, shape, or form. ^^