Tsukasa's ass-kicking and generally awesome older sister.

Tsubaki is Tsukasa's sister. She is one of the few people who is not afraid to stand up to him, a trait that Domyoji secretly admires in her. She marries the wealthy heir to a hotel company and moved to Los Angeles with him. Although she has obtained a degree of happiness in her marriage, she did not choose her husband and was manipulated by her mother Kaede into breaking off her relationship with an ordinary boy she loved and marrying to suit the family interests. She begs Domyoji not to make the same mistake.