Sad lullaby for Rika

Title should explain it

The song that described, how they felt.When their mother left, and didn't come back.

Rika describes this song as her very life, Tamaki had played it every night to help her sleep.She never forgets the song and is secretly trying to write lyrics for it, and give it to her brother for their birthday in a couple days.

What Rika explains as the song to remember forever, a song that Tamaki and Rika's mother wrote before she left.

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