Rika Kawada

Yura's 20-year-old sister. Sexually experienced and rather promiscuous (to the point where, early in the series, she keeps a boyfriend and three "sex friends" – in addition to miscellaneous flings), she constantly teases and goads both Makoto and Yura into improving their "night life". At first in an on-and-off relationship with her "number-one boyfriend", Taku Yamada, for most of the series, she eventually decides to settle down, even marrying the son of Makoto's boss Katori, though their matrimony rapidly disintegrates soon afterwards following personal differences. Is very experienced in relations with men, by far, had 30 sex partners. Now has 4 boyfriends. Is somehow worried about the married life of her elder sister and gives her advice about making love.