Rui
Rui is a maid to the Kougami family. She often follows her mother around to assist. She makes her first appearance in Volume 3. She is in love with Megumi, who rejected her for Suzuka. It is shown in a flashback that Megumi treated her as a substitute for Suzuka, when he heard of the Kougami family's death (with the exception being Suzuka). She comes back to the Kougami mansion, thinking that Megumi will marry her, and got into a fight with Suzuka over Megumi http://en.wikipedia.org/wiki/Captive_Hearts_(manga)#Characters