Other name: 僕らの恋は死にいたる病のようで, 我们的爱如绝症一般, 無可救藥的愛情, Bokura no Koi wa Shi ni Itaru Yamai no Youde, Our Love is as Painful as Reaching Death
Summary: As children, Aki became acquainted with a four-year old Akane. Meanwhile, Sora confessed to Akane that he'll propose to her when she turns 18. Unfortunately, he died in a traffic accident. He then appears before Akane, Masaru, Aki's younger twin, with the voice, figure and everything else like him. Akane, had to confront the twisted love and affection given to her by Masaru, instead of Aki from...?!