I looked up on the GTS a Pikachu and a picture showes a lv 7 Reshiram (nicknamed Pikachu Gender:boy)is this even real?
Obviously so.
It's a LV 7 Reshiram.
It has a gender.
I think it's a clone glitch. (Can't get to source on Bulbapedia due to server issue, but you can search "clone glitch" on Bulbapedia.)
Yes. It is a glitch in the GTS. Nobody knows how it occurs. People use it to trick fools to give legendaries to them for free.