I was excited as crap when I heard about Gen 5 and saw the starters. I used to always pick the fire-type no matter what and I was pretty sure that was gonna be the case for B/W. But I could not picture at all what Snivy was going to turn into. And when I finally did I was blown away and couldnt resist not picking it when I was building a party for Black. I adapted well to its stats/moveset and it became one of my all around best Pokes in game/online.
It wasnt until well after B/Ws release that I saw the Smugleaf meme (I barely bothered w/ the internet back then). And my adoration for Snivy/Serperior sky rocketed from there
Charizard. My first Pokemon card was a Charmander card, my first Pokemon game was Red version, so obviously I started with Charmander to get Charizard. The anime also helped, not surprisingly. My affinity for the line, and Charizard in particular, has to do with my love of dinosaurs, dragons, monsters, etc. I had as a child (and still have, to be perfectly honest). Most of the time I see a reptilian, saurian, or draconic Pokemon I get excited and want to use it, but Charizard just happens to be my first partner, thus it gets the most love.
Sableye. HE'S so freaking cute. The lil gremlin. I was estatic when he got prankster. He's also able to learn Metronome (my favorite move) and abuse it with Prankster. I hope he gets an evolution in gen6 so I can give him the eviolite.