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Yori Yuki:[/b] The older twin brother who is in love with his twin sister Iku. Yori used to be a very carefree character before he realised his feelings for Iku that were unnatural. His attitude suddenly changes and Iku is left in the dark, the reason being that he is in love with her and wants to be her lover and give her the life of a normal couple. In the live action movie Yori is played by actor: Jun Matsumoto.

Iku Yuki: The younger female twin is a very heartfelt and genuine character that loves her brother as her brother. She realises that her brother has feelings for her that are more than the normal brotherly and sisterly love. In the live action movie Iku is played by actor: Nana Eikura.

Haruka Yano: Is the best friend of Yori and is always by his side. Even though Yori doesn't realise it, Haruka knows his feelings for his sister and thought that it was better for Yori to tell him by himself.And as the chapters progress, he develops feelings for Iku, and lets Yori know about it. In the live action movie Haruka is played by Yûta Hiraoka.

Tomoka Kusunoki: Is in love with Yori. She expresses her feelings toward him early in the movie and Yori tries to love Tomoka. This was all in vain because the only reason for what Yori and Tomoka shared was so Yori could forget about his true love - Iku. In the live action movie Tomoka is played by: Ayaka Komatsu