This story takes lead of some teenagers (Yeah ikr) who has into some catastrophic disaster of the disease called Hanahaki, it's a disease where when one loves a person romantically while the other loves them back but their friendship is not enough to prove ones love to the other.
Example:
A person loves back at some and so they love them back, but since their friendship is not enough to prove their love, the one who started it will be the one who gets the disease.
This love can also be secret love too, like when someone loves them romantically but cannot say to the other, while the other has the same way, they share the same love but not enough friendship to grow the love further.
meaning that this disease is caused when taking a shortcut through love, it takes time meaning you have to grow the friendship before when having love through someone else.
life doesn't have shortcuts meaning this fictional disease prevents people from taking shortcuts through life, you have to understand the person before loving them back.
you may like them but you cannot force yourself yet to them or else you'll have to pay the price of your life.
this disease may be cured from surgical removal but that means the one who had the disease will loose the love they have from that person, meaning that they have to start all over again.
so yeah, this story involves BL within Hanahaki, so ye.
that's the full explanation to Hanahaki, so enjoy my story!