Kyoya Otori

Japanese name:	鳳 鏡夜
Nickname:	Mommy, Shadow Prince, Low Blood Pressure Demon Lord

Kyoya is best friends with Tamaki, despite their completely different demeanors. At times he is described as "just as reckless as Tamaki." Tamaki tends to call him "Mama," in reference to Tamaki calling himself "Daddy." Kyoya is secretive and intelligent, being able to calculate any benefits that would come out of the Host Club's misadventures. Kyoya is a very realistic and pragmatic teen who takes everything for granted and gets things in return. He is very accurate in all things especially when it comes to money or finances. Despite having quite antagonistic traits, the Host Club wouldn't be as half as successful without Kyoya's uptight resourcefulness. Although he doesn't put on an act for the women, he is considered the "cool type."[15] He lives with his father, an affluent zaibatsu owner specializing in hospital management, two brothers that he has to surpass to become his father's successor, and an older sister who deeply cares about him. Although he comes off as cold and uncaring, there have been instances in both the anime and the manga wherein he shows concern for others. One instance was when the Host Club went to the beach, and he pretended to be "the bad guy" just so that he could show Haruhi how worried she made everyone. Another was when he helped an old lady who was about to pay a large amount of money for a fake item. Also in book six he tries to help get Tamaki in better graces with his grandmother. He is worried about Tamaki and arranges for Tamaki to meet his mother.

Wiki