I got warned because I did a thread like this... if you have a question, ask it in Simple Questions. There you'll find the best peeps to answer anything you're confused about. ;-)
PkRS is Pokerus... it's a virus that will double your EVs obtained in a battle. You're part of the Elite Pokerus Club, along with myself, considering it is extremely rare (rarer than a shiny, if I'm correct). It spread to other Pokes in your team, so be sure to store a few infected in your PC to save it, because it eventually dies off (I've noticed it lasts longer depending on the Poke - my Metegross has it for about three days, but my Steelix had it for almost 5. No clue!).