Watch Ao no Hon

17-year-old Shuichi Kushimoro enjoys his simple life with his mother and sister. But everything begins to go sour when Shuichi's long absent stepfather, Sone, returns to the house. Soon, Sone's drinking is out of control and he begins to make unwanted advances towards his stepdaughter. Determined to defend his sister's honor, Shuichi decides to take care of the problem once and for all, but worries when the police begin to connect him to Sone's murder.