In the Court of the Blind King

After a long time suffering his unending punishment dealt by Gold Experience Requiem, Diavolo is given a chance of redemption. He wakes up in a large room alongside a young man. Upon further inspection, he realises the young man is Doppio, now separated from him and in his own body.
A group of cloaked people appear and explain to Diavolo and Doppio that they must complete 6 trials to achieve his peace. However, his stand, King Crimson, has been separated from his Epitaph, which is now under control of Doppio, with a body of its own.
Now, Diavolo and Doppio must face the trials and survive, so they can finally achieve peace. But he must be careful, as the trials will pose him a hard challange, and he must learn to work alonside Doppio, for without Epitaph under his control, his own King Crimson is blind.

This story follows the character Diavolo after his fate in the end of JoJo's Bizarre Adventure Part 5: Vento Aureo, so it is suggested that the reader has finished that part before reading this.