which series does it belong to?
"Grey's Anatomy"
Callie Torres
 Iphegenia Torres, M.D. is a fictional character from the medical drama television series "Grey's Anatomy", which airs on the ABC in the United States. 
when does callie get pregnant on grey's anatomy She moves in with Sloan, and they have a one-night stand. Robbins returns for Torres, apologizing and hoping for forgiveness, but Torres initially rebuffs her, and later reveals that she is pregnant with Sloan's baby who created this character? Shonda Rhimes
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Callie Torres [SEP] Introduction
Calliope Iphegenia Torres, M.D. is a fictional character from the medical drama television series "Grey's Anatomy", which airs on the ABC in the United States. The character was created by series' producer Shonda Rhimes, and is portrayed by Sara Ramirez. She was introduced in season 2, as a senior orthopedic resident, as a love-interest for intern George O'Malley (T. R. Knight). Eventually becoming an attending orthopedic surgeon, the character was originally contracted to appear on a recurring basis, but received star-billing in season 3. Torres was initially conceived as a love-interest, and eventual wife, for O'Malley, and was created to be disliked by her colleagues.