To clarify, I meant that each sketch probably had a story behind it, as opposed to all the sketches collectively having a story. Just in case that wasn't clear.
The Tepig/half-hearted Treecko pair is actually my most recent drawing of the whole thing. In fact, I drew it the same day I uploaded those, yesterday. They're the player character and partner character of my playthrough of Super Mystery Dungeon, respectively. I lost interest while sketching the Treecko, as you can probably tell.