Pokémon Black & White
Offscreen, Emile captured a Level 5 female Lillipup, which he nicknamed Lillipop, to trade with MasaeAnela to show off the game's infrared trade system. In return, he received a Level 3 female Lillipup named Berk, and he mentioned that doing this trade would set some things up for later in the game.
Emile revealed that the reason he had done this was to show off Unity Tower. He learned the hard way that the trade had to occur in the Union Room, and subsequently traded and traded back their respective Lillipup offscreen.
Berk, along with the rest of Emile's catalog of Pokémon, was seen in the PC when Emile was looking for a Pokémon to teach Fly.
Berk has a Naïve Nature, which neither helps nor hinders any stats.