Crystal disease is caused by inner depression after lovelorn. The patient's skin will slowly grow crystals. The color of crystal is the lover's favorite color, which is connected with the skin. If forcibly removed, it will be very painful, and eventually the patient will die when the crystals are all over the body.
Being a butterfly is the most beautiful disease. There will be a butterfly spot under the right corner of the eye. The color is determined by the color of the eyes. There is no antidote. How many butterflies will that person you love become? Every patient who becomes a butterfly is a feast.
Spitting flowers is a happy and cruel disease. The antidote is to let the person you like kiss you, and you will be cured and never spit out petals again. This is happiness. If you don't get the antidote, you will vomit and die. This is cruel.
Gem blindness simply means that a person's eyes will become the color of another person he likes. If I kiss, if I can't get that kiss, I will go blind. This is also the origin of the name Gem Blindness.
Mermaid amnesia is a cross-species disease. If you love someone enough, your legs will turn into fishtails and you will be extremely short of water. The antidote is still the kiss. If you don't get it, you will become a mermaid forever and lose all your memories.
These are just the settings in the novel, but they don't exist in real life. Please don't believe it!
The color of love is colorful ... probably.