A/N: This is an idea inspired by the fanfic Bedside Manners so give credit to the author of that story but this is a little darker.
1:34 RWBY's dorm corridor.
Weiss was heading to their dorm after talking to Ms. Goodwitch about her sparing match with Cardin who she was claiming to have cheated in the fight Glynda said she would look into it but not until tomorrow. Weiss satisfied with this was on her way to her team's dorm, once she entered she noticed Blake and Yang weren't there, they must have gone somewhere together. But what she was most concerned with was that Ruby was still in bed, Ruby was never asleep for this long. "Ruby?" Weiss asked in a worried tone, "You alright?" no reply. "Ruby you need to wake up" Weiss said nudging her leader. Ruby opened her eyes and Weiss was shocked to see that they were blood-shot. "Ruby are you okay?" Weiss asked even more worried than before. "I'm okay" Ruby replied her nothing more than a whisper. "Are you sure?" Weiss asked. "I'm fine" Ruby said as she slowly dropped down from her bed "I'm feeling better than ever come on let's go train." Ruby said as cheerily as she could even though her voice wasn't any better. Weiss was still sceptical about her partner's health but trusted that she knew what she was doing. This trust was about to be destroyed when as they were heading down the corridor Ruby collapsed into a heap on the floor. "RUBY" Weiss screamed in panic as she ran to her partner who was currently unconscious on the floor "HELP ME SOMEBODY HELP ME" Weiss screamed.
Beacons Infirmary two days later.
Ruby opened her eyes slowly she felt awful, she didn't know where she was or why she was here. But it seemed like she was about to find out considering how the first thing she saw was her sisters concerned face in front of hers. "Hey Sis, how you feelin?" Yang asked she sounded very worried. Ruby didn't know why but maybe it had something to do with how awful she felt. She went to sit up but Yang stopped her but before she did Ruby noticed that Weiss was next to her and Blake was leaning on the wall in front of the bed she was in, they both had a worried expression on her face.
The day before.
"How could this happen?" Yang asked the nurse sobbing. "I'm not sure but I've seen this once before and I've read about it it's a disease that is very rare and only affects a small number of people." "So what's the good news?" Yang asked holding back tears as she was sitting next to her sister who was currently unconscious. "I'm sorry to say there is no good news, the survival rate of this kind of disease is little to none." It was at this point were Yang could not hold back hearing that her sister was most likely going to die just made her break down. Weiss and Blake just couldn't believe what they had just been told, their leader was sick and most likely dying they didn't know how to react.
Present time.
"Hey, how are you guys?" Ruby asked her voice even worse than before. "Never mind us, how are you feeling?" Blake asked hiding her sadness from view. "I'm not feeling as good as I wish I was." Ruby replied. The sentence almost made Weiss bawl because she knew Ruby had no idea about how serious her situation was. The group stayed silent for what felt like years to the friends. "Ruby" Yang said eventually blinking back tears. "Yes" Ruby answered, "I have to tell you something about your condition." Yang said her sadness more obvious now. "What, what do you have to tell me?" Ruby asked sounding slightly worried. Yang didn't know if she could bring herself to answer, the only thing allowing her to know the passage of time was from the steady beep coming from Ruby's heart monitor. Beep, Beep, Beep, Beep. "R, Ruby what I have to tell you is-"
Beep, Beep, Beeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-
The monitor started making a continuous noise. "NO!" Yang screamed looking up to see her sister blankly staring at the infirmary's ceiling. "NO RUBY PLEASE NO DON'T DIE ON ME" Yang screamed as she cried. Weiss and Blake were too shocked by the realisation of what had happened to react. "RUBY NO" Yang cried, "WE WERE SUPPOSED TO BECOME HUNTRESS'S TOGHETHER PLEASE, PLEASE DON'T" Yang went quiet "Please just don't leave me alone" Yang said quietly before hugging her sisters motionless body.