Touzouku to Houseki Shoujo

Azusa, known as the 'jewel girl' is one of the few remaining, living members of her family, that was gifted with a unique ability - according to her own emotions, she can turn flowers and plants into precious jewels. Held captive and working for one of the country's Lords for 10 years, the only thing she was looking forward to was catching a glimpse of the Lord's second son who was very kind to her.
But now, that the boy has suddenly disappeared, her ability has started to diminish. Azusa runs away to find him, only to stumble upon Monji, a young thief who makes an interesting deal with her.