Gensokyo 20XXV: New Beginnings (AKA Apartment Gensokyo)

Sometimes, Koishi wanders about the place but, this time, she came home and, as she wrapped her arms around me, I had noticed she was bleeding. She collapsed in my arms and I hurried her over to Kaguya. It was over three hours and Kaguya came out with a somber look on her face. She summoned everyone else into the hall and said, "I am sorry I have disturbed you all at such short notice but I am sad to inform you that I have done all I really could and it may be a matter of time before Koishi passes away and it hard to say how long she will survive." I was in tears and sobbed hysterically, before bringing her back to my apartment and letting her sleep in her bed. I closed the curtains and turned off the lights. She never could arise out of bed and I had given her the painkillers Kaguya has prescribed.

As I had given her those painkillers, I started to feel horrible. She was already dying and I had selfishly been trying to end her life sooner because I couldn't take it. I was murdering my sister and, as a result, I was murdering myself. After that, I stop giving her the pills, leaving her to suffer in pain. I couldn't bear to watch her suffer but, at the same time, I couldn't face the thought of killing my sister. She was my only family, the only thing I have left, and if she died, then I'll be alone but to allow her to live in this state would be allowing her to suffer.

I knew not really what to do. Should I let her suffer or should I take her life as an act of mercy?
_________________________
"Still blind?"

"Yes, dumbass."