One More Day was event in the Spiderman comics. It proved to near-universally panned.
The basic plot is that Aunt May is shot (the bullet was meant for Spiderman). So, Spiderman seeks the help of the greatest scientists in the Marvel Universe, who can't help a bullet wound. Mephisto (the Marvel stand-in for the devil) offers Spiderman to save Aunt May exchange for his marriage with Mary Jane and agrees on the ground the Mephisto will erase the memories of Spiderman revealing his identity.
This event was praised for it's art, but criticized for it's writing. I haven't read it, but I have a few questions: 1. Why can't the greatest scienists in the Marvel Universe mend to a bullet wound? 2. Why does Mephisto want their marriage and not their souls? 3) How can Mephisto do this? He never shown any powers remotely like this before.
My source was Wikipedia.