The Fall of the House of Usher
Roderick and Madeline
Roderick and his sister make a great foil pair. Male and female, alive and dead, earthly and spiritual are some pairings to get you started. Consider the nature of their illnesses as well: Madeline’s is a largely physical illness, while Roderick’s may be largely psychological. (His acute senses may just be the result of his hypochondria).