The Hanahaki Disease is a made up disease of which a flower, specifically a cherry blossom, would grow in a victim's lungs. The victim would often cough up flower petals and blood as the flower grew inside them. The worst part is, you could potentially die if you do not take matters into your own hands. The reason this happens is because the one they love is in love with another, or they just generally do not feel the same way. The only way to cure it is to kiss the one you love meaningfully.