紅白曼珠沙歌 (Kouhaku Manjusha Uta)

Background
This song is featured in the album Boku to Kimi to no Jikan Ryokou (ボクとキミとの時間旅行) and Astrologia no Juuni no Sign and has entered the Hall of Fame. Note that despite the fact that one of the twins is represented by Len, they are both supposed to be women.

It tells the story of a pair of twins in a brothel, calling themselves the "Crimson (Rin) and White (Len) Spider Lilies". The twins carve in a symbol on the back of their necks as a promise to care for each other even if one of them is sold off. This eventually happens to the Crimson Lily and the White Lily comforts her, wishing her to find happiness, but before the man arrives in the morning they have sex and confess that they love each other. As soon and the Crimson Lily is gone, the White Lily reveals that she's though of her sister as nothing but a nuisance and cuts her symbol, declaring the brothel her domain.

Lyrics
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