Puella Magi ☆ Kenko Magica

Puella Magi ☆ Kenko Magica is a one-shot spin-off of Mary Sue Magica made for Halloween that expands the story on Kenko Tsukino, the Magical Girl that mentored the infamous Niji Akemi became Nelly. I had to put a disclaimer in case I accidently offend people with mental illnesses.

It can be read here

Plot Summary
Kenko recounts on how she made a contract with Kyubey after discovering her older brother, Hoshi, was a drug addict that threatened to kill her if she told anyone about it. After the contract is forged, Hoshi confesses his crimes to the police is put into a juvenile detention center for six months. At some point, Kenko met a newcomer Magical Girl named Niji and helped her battle a Witch. Albeit, she can only vaguely remember parts of the battle. Once Hoshi is released, she tells him about how she used her Wish to free him from his addiction, leaving him confused. She can't even show Kyubey to him. Later on, she starts telling more and more people that she's a Magical Girl. At first to rationalize being late or absent from school, but later she does it just because she's excited about her duties. It got to the point where she was tested to make sure she didn't have any medical conditons, and it's not helped that the inkblots remind her of Witches. Things started to get ugly after her parents checked her into the psychiatric ward of Mitakihara Hospital after being diagnosed. She tried resuming to her work ,but she was later locked in at night after the staff discovered that she keeps leaving the hospital grounds. She got more and more frustrated as nobody believes she's insane, until becoming a Witch called Nelly. She is quickly defeated by her former comrade and laments on how she has the need to scream even though she no longer has a body.

From Canon
Kyubey

Fanmade

 * Kenko Tsukino/Nellie
 * Niji Akemi
 * Hoshi Tsukino
 * Sigmund and Florence's, Nelly's familiars

Trivia

 * The last line is referencing "I Have No Mouth And I Must Scream" by Harlan Ellison.
 * I chose drugs as the cause for Kenko wanting to make a contract to foreshadow how her sanity starts slipping.
 * Originally Niji only appeared at the end ,but was re-written after deciding to make Kenko Niji's mentor. And it was honestly a change for the better.