@That One Guy  
Shining is way too nice to be Undyne.
 
If anything, he’d just be a second Papyrus.
 
Or maybe one of the guard dogs.

@Keith Mowz  
I suppose. Though I am confident that Papyrus would be a close second.

>This…
 

 
 
_^>this…

@That One Guy  
The closest 1:1 is Rainbow Dash as Undyne. Everyone else is a combination of ponies.

@PonyPon  
Shining Armor? I mean, he’s actually a Captain.  
Or maybe one of the Wonderbolts. Spitfire, probably. After all, nothing constrains us to the Mane Six.

@That One Guy  
But then who’s gonna be Undyne, the one who is also already a guard?

I never understand how people don’t connect Papyrus’s self-image to the similarities in RD’s.  
Both loyal, narcissistic to an extent, determined, think highly of their skills…

The pony skeleton designs are surprisingly…accurate.

…okay