Splinter, often referred to as Master Splinter or Sensei by his students/sons, is a fictional character from Teenage Mutant Ninja Turtles comics and all related media. A mutant rat, he is the grave and stoic sage of the Turtles, their ninjutsu and martial arts instructor, and their adoptive father. The character was originally a parody of the Marvel Comics character Stick. Source: Wikipedia (en)