Quirk of Fate

What if it had been Mary Jane Watson who had gotten bitten by the radioactive spider, and not Peter Parker?

This fanfiction series written by "the Master Planner", set in an alternate universe where, due to a single quirk of fate, Mary Jane is the one who receives the spider-bite. At first freaked out by her newfound powers, she soon decides to become a costumed superhero, partly out of a desire to help people but mostly because it seems like fun. At first she enjoys the thrill of her new abilities as the spectacular Spider-Woman, but when she encounters her first supervillain in Doctor Octopus, tragedy strikes and she is forced to learn just how much great power requires great responsibility.

First started in 2006, the series now comprises almost fifty chapters that follow Mary Jane's growth as a heroine and her encounters with different enemies. Shout Outs abound with tributes to the original plotlines, and unique spins on classic characters. With a spare, straightforward writing style, the series is accessible to newbies and continuity buffs alike, and comprises both stand-alone stories and an ongoing storyline that links them all together as Mary Jane starts in high school and continues into university.

The story so far is in five volumes:

Tropes used in Quirk of Fate include:

Adaptation Distillation: No deals with the devil, no spider totems, no superhuman registration, just classic two-fisted spider-action and character development with a modern twist.
Alternate Character Interpretation: Characters like Peter Parker, Mary Jane and Doctor Octopus are more or less the same as their canon versions. Characters like Curt Connors, the Green Goblin, and Venom are drastically reimagined, however.
Alternate Universe Fic
Arch Enemy: Doctor Octopus is the main bad guy in this story rather than the Green Goblin, mostly due to the author's preference.
Author Appeal: The author is a huge Doctor Octopus fan, and has made him Spider-Woman's archenemy, as opposed to the Green Goblin or Venom, and also accounts for the Doctor's recurring appearances.
Bittersweet Ending: The first story arc ends with Doctor Octopus defeated, but Mary Jane is left to seriously question her role as Spider-Woman after Doctor Octopus horribly murders someone she cares about.
Death by Origin Story: Ben Parker doesn't die in this one, but the loss of someone close to her forces Mary Jane to grow up and realize that being a superhero isn't all fun and games.
Distaff Counterpart: Spider-Woman is the most obvious one, but the second Doctor Octopus, the Scorpion, and Venom are all female in this version.
Easter Egg: There are lots of tributes here to the classic comics.
Official Couple: Subverted. Think Mary Jane and Peter are destined to live happily ever after? Think again.
Ordinary High School Student: Mary Jane starts out as one of these before the spider bite. Peter Parker stays as one of these all through the series.
Pick on Someone Your Own Size: Doctor Octopus is initially attracted to Spider-Woman, but this turns into poisonous, obsessive hate when she flatly rejects him. This trope also applies to J. Jonah Jameson, whose frenzied loathing of Spider-Woman matches anything the 616 Jameson ever came up with.
Redheaded Hero: Who do you think?
Plucky Girl: See above.
Rogues Gallery: Doctor Octopus, the Green Goblin and Venom have already appeared. Word of God from the author notes that the Lizard, Mysterio and Electro will be appearing in future segments.
Shout-Out: Continuity buffs will find lots of tributes to the classic Lee/Ditko/Romita comics.
Stalker with a Crush: According to the author, Electro is going to be one of these.
Ten-Minute Retirement: The tragic results of her first encounter with Doctor Octopus make Mary Jane give up her career as Spider-Woman in shame. She dons the webs once again when the people she cares about are put in serious danger by her enemies.
Villain Team-Up: The Sinister Six are planned for a future story arc.