Kyousuke, who lost his partner Kai in an accident just before their major debut, has distanced himself from music and lived listlessly. But three years after the accident, Kai suddenly appeared before Kyousuke. 

"Even if you're alive, if you just stop and do nothing, it's the same as being dead, right?" 

 His blunt, unfiltered way of speaking was unchanged from before his death. And his forcefulness made Kyousuke smile against his will. Persuaded by Kai, Kyousuke confronts the world of music once more and rediscovers the joy of creating sound together.
 
But the happy times with Kai wouldn't last forever... 
(Source: Crunchyroll News, edited)

Kyoukai no Melody