To Love Ru Darkness Vol. 4

Among all the lovely ladies surrounding Yuki Rito, the deadly assassin Yami has always been a breed apart--aloof, dangerous, and haunted by the secrets of her past. When one of Lala's inventions goes awry, Rito and Yami have no choice but to spend a whole lot of alone time together. Has the time finally come for Rito to learn about Yami's secret history?