U+U=W is the first and only essay book by W. It was released on December 4, 2004 by Takeshobo.
Publisher's Description[]
Four months since Morning Musume's August "Smiles and Tears Graduation," the "Genius?! Personality" Tsuji Nozomi and Kago Ai have released an autobiographical narrative as they begin their activities as W in earnest. Tsuji Nozomi and Kago Ai discuss topics like "Being Yourself," "Morning Musume," and "Friend Stuff." And as they get into their dialogue, there's plenty of "they're not twins, but they're like twins" in this unprecedented miracle collaboration book!!