Commonly used by 14-year-old British bitches on the Internet as a replacement for "me" in attempt to sound fancy and British. Other fancy-sounding variants include "ish", "dis", "mah", "fren" (friend).
These type of kids tend to overuse text emotes such as "XD" or ";-;" (crying face) to the point where you're contemplating suicide.
Me: Are you actually retarted?
14-year-old: Nuh! Meh ish not XD