Kiss ha Naisho ni

When Ayumi's dad remarried, he brought home not only a new mom for Ayumi, but an older brother too! Takeru's handsome, nice, and really popular with the girls. So popular that his phone never stops ringing! Ayumi can't help but be bothered by his popularity, but if he's a player why should Ayumi care? Isn't it wrong for siblings to have those kinds of feelings for one another?