Origin
El Toro’s wife had a drug abuse problem which lead to her getting sick. El Toro prayed to god and the devil to save her, but neither responsed, then when she died he made a deal with a demon. As long as El Toro fed the demon pieces of people the demon gave him the power to take down the drug trade in Mexico.
Creation
El Toro was created by Simon Sanchez for his series Kung Fu Satanist.
Major Story Arcs
Kung Fu Satanist: El Toro
For more information see: Kung Fu Satanist #2
El Toro sent his hired goons to stake out the Zero Club in Cozumel, Mexico during spring break and kidnap some party goers. The hired goons brought back 4 rich spoiled brats and after roughing them up a bit, El Toro cut off the one guys leg for his demon master.
Later when Arthur Brown comes to Cozumel looking for the missing people, El Toro kidnaps his girlfriend, Madeline. He then has her possessed by a demon so she can fight Arthur and his demon Iska.
When it looked like Arthur had won and freed Madeline from her possession, El Toro snaped Madeline neck which causes Arthur to rage and rip out El Toro’s heart and feed it to Iska.