the hanahaki disease is an illness born from unrequited love, where the patient's throat will fill up with flower, they will then proceed to throw, and cough up the petals. one of the only ways for the disease to 'disappear' is if, the said person returns the feeling, it can't be resolved with friendship, it has to be genuine feelings of love. The infection can also be removed through surgery, though the feelings disappear along with the petals. If they choose nether options, or the feeling is not returned in time, then the patient's lungs will fill up with flowers, and will eventually suffocate.
after waking up in the middle of the night because of a small stomach, kurt hummel finds himself hunched over the toilet bowl throwing up red roses. he knew right away what it was, hanahaki disease. how was he supposed to tell mercedes jones, one of his best friends that he was in love with her boyfriend sam evans and he knew rachel berry wouldn't keep his mouth shut. theirs one person he can turn to, blaine anderson.