Your Lie in April
When Kaori comes back from the hospital, she invites Kōsei to play at a Gala with her. Kaori doesn't show up on the day of the Gala. As her health gets worse, she begins to give up on life and wants to kill herself. Kousei helps her keep going by playing a duet with Nagi Aiza, the sister of a fellow rival of his. After this, Kaori chooses to have a dangerous surgery that will kill her if it fails, just so that she can play with him one more time.