You are the biological son/daughter of Splinter. After he rescued the turtles he went into hiding in the sewers and you were left to fend for yourself as a child. At the age of 17 you graduated college and joined the foot clan, eventually leaving in search of your father. Characters included: Raphael, Leonardo, Donatello, Michaelangelo, Splinter, April

You are running from the foot clan who you have just abandoned and are hiding in the sewers