Hanahaki Disease Short Story

Hanahaki is a mythical disease. When someone who has dedicated all their heart and
soul into the relationship doesn't have their feelings returned,
a flower starts to grow inside of them.
You can prevent their death by having a surgery done
to remove the root, but they will be rendered emotionless or forget the person they loved.
Unless the person returns the feelings, the disease will slowly
and painfully kill them from the inside out.
But sometimes, it is too late...

(This takes place in an alternate universe where you have a string connecting you to your soulmate. You can only see it when you turn 18. If it turns black, your soulmate has rejected the bond. The recipient then develops Hanahaki, but the person that rejected the bond can still fall in love with someone else. If both reject the bond, neither will ever be able to love anyone. If the bond is accepted, the string turns turquoise and you will meet your soulmate within the next 24 hours.)