One of the three main characters in VN's novel Pale Fire (1962) is Jakob Gradus (Shade's murderer). At the end of his commentary to Shade's poem Kinbote (who imagines that he is Charles the Beloved, the last self-exiled king of Zembla) mentions a bigger, more respectable, more competent Gradus:
"And you, what will you be doing with yourself, poor King, poor Kinbote?" a gentle young voice may inquire.