Diamond is Unbreakable - Chapter 54 
Let's Go to the Manga Artist's House, Part 2 (漫画家のうちへ遊びに行こう その② Mangaka no Uchi e Asobi ni Ikou Sono 2), originally The Best Source Material! (最高のネタ！ Saikō no Neta!) in the WSJ release, is the fifty-fourth chapter of Diamond is Unbreakable and the three hundred nineteenth chapter of the JoJo's Bizarre Adventure manga.
When Rohan leaves his workplace, Hazamada and Koichi decide to take a peek at the newest chapter that Rohan has just finished drawing. After they witness the greatness of Rohan's manuscripts, the manga artist enters the room and uses the ability of his Stand, Heaven's Door, to open Koichi's face like a book and look at his story. After he discovers that Koichi also has a Stand and learns of his adventures with Josuke and Okuyasu, he says that he has finally found the perfect inspiration for his comics.