Figured I'd give a plot layout. Just for fun.
"Episode" length: 50 main chapters (+ 6 extra chapters (prologue and side character check ins)
Time placement: About 2 years after Mato's defection. The story happens over the course of a year, starting on Mato's 23rd birthday.
Prologue: Details on the history of the story and explains the origins of the main quintet of characters.
Arc 1: A Star's Choice
Part 1 (EPS 1-5) is about Mato traveling from place to place as she attempts to remain on the run and off radar. She fights and saves people along the way.
Part 2 (EPS 6-10) has Mato entering a small city, before her exhaustion forces her to stay with a family until she recovers. She ultimately saves them and makes the choice to stay with the family for the near future.
Extra 1: The UNPF assembles Chariot, Strength, Dead Master, and Black Gold Saw, announcing that Mato's been located and that she needs to be either apprehended or killed.
Arc 2: Friend And Foe
EP 11: Kagari aka Chariot enters the city in search of Mato, who's attempting to find a job to help the family as a way of thanks. Mato succeeds in forcing her to retreat, but knows that her former allies will be making appearances.
EPS 12-13: Yuu aka Strength enters the city, finding Mato in the city's main park. At first, the two have some simple small talk about their families, before Yuu accuses Mato of being a traitor. This leads to a scuffle, which Mato wins thanks to aid from local police. After Yuu leaves, Mato returns to the family, before sharing with them about her past.
EPS 14-16: Yomi aka Dead Master enters the city, before setting up a sniping position. Eventually, she finds Mato and prepares to kill her, only for her to suddenly fire a warning shot. This alerts Mato of Yomi's location and the two get into a battle, which ultimately test whether or not Yomi is still herself. Mato loses, but Yomi can't bring herself to kill her old friend, so she runs, leaving Mato in a mix of confusion and hope.
EPS 17-20: Saya aka Black Gold Saw enters the city, finding her during lunch hour. The two have a friendly discussion, before Mato brings her former commander to meet the family. Eventually, Saya explains to Mato her current situation, which results in a duel to see if Mato can truly handle her lonely battle. Saya wins, but believes Mato's proven her determination, agreeing to help in secret whenever possible...after she teases the younger woman a bit.
Extra 2: Upon returning to base, Saya is brought to the engineering room to witness a startling sight. White Rock Shooter is born.
Arc 3: Unleash The Beasts
Part 1 (EPS 21-23) has Kagari, Yuu, and Yomi working together to apprehend Mato. At first, things are going well for them, until Saya steps in. Saya then fights Mato, who loses, and brings her sword towards the younger woman's chest, striking shock and potential fear into her. Saya then single-handedly defeats the other three girls, forcing them to retreat. Saya then apologizes to Mato, explaining that she too has defected to help the younger woman, much to Mato's joy.
Part 2 (EPS 24-26) has the trio return, using their Beast forms this time. Mato and Saya retaliate with their Beast forms, which results in a standstill between them. Saya manages to devise a strategy which helps both of them successfully hold the trio off until the Beast forms' time limit expires. Yomi once again attempts to shot her old friend, only to have a mental breakdown, causing her to go unconscious. As Yuu and Kagari leave, Mato brings Yomi to a hospital.
Part 3 (EPS 27-29) has Saya watch after Yomi, while Mato explains the situation to the family that had adopted her. The family agrees to help however they can. Yomi attempts to break free from her psychotic personality. Mato encounters WRS, who easily forces her to use her Beast form, only to easily get defeated by WRS's own Beast form. The clone retreats, wanting to toy with Mato a little longer. Yomi awakes, her mind healed, thus reuniting with Saya and Mato.
EP 30: Mato and Yomi catch up on lost time. Yomi meets the family Mato settled with. The sniper finds herself having recurring nightmares and dark thoughts, which leads her to getting therapy. But she's healing. The three woman are indeed healing.
Extra 3: The UNPF deems the WRS project a failure, causing WRS to revolt and destroy their leaders in search of her own goals. The Jikken Army takes this opportunity to apprehend Kagami and Yuu and take out the rest of the UNPF.
Arc 4: Chaos and Insanity
Part 1 (EPS 31-35) has Mato, Saya, and Yomi recuperating, before being ambushed by the Jikken Army. After helping evacuate the family and surrounding civilians, the trio defeats each squad that comes after them. Eventually, they encounter Yuu and Kagami. After a lengthy battle, Yuu and Kagami surrender, allowing the trio to bring them to a hospital and psychiatric facility.
Extra 4: Yuu and Kagami eventually heal, before Saya takes them to her home for the time being. A few months pass. Yomi is a librarian. Saya is a teacher. Yuu and Kagami are job searching. Mato is still at her current job. Things are peaceful as UNPF and Jikken Army dissolve and are shut down.
Part 2 (EPS 36-40) has WRS track down the quintet, forcing them to seek shelter somewhere away from their homes. Mato brings them to their hometown and her old home, giving them time to make a strategy and get supplies. The group attempt to take down the clone in Beast form, but are still outmatched. Saya and Mato are forced to use Insane form, successfully driving WRS off. Unfortunately, Saya has to forcibly subdue the younger woman as her Insane form begins going rampant. After Mato comes to, she gives her parents and brother's graves one more visit, before heading back with the others.
Arc 5: The Fated Duel
Extra 5: Mato's 24th birthday arrives and the group reminisce on the past year. WRS, meanwhile, develops a parasitic virus that will hopefully kill her original counterpart even if WRS is killed too.
Part 1 (EPS 41-42) has Saya returns home, before her, Yuu, and Kagami are ambushed by WRS. Saya successfully manages to kill her, unaware that the parasite has been injected into her body. The parasite takes its time separating Saya's consciousness from her body, before taking complete control.
Part 2 (EPS 43-45) has Mato and Yomi enter Saya's home to see Yuu and Kagami beaten within an inch of their lives. Saya's nowhere in sight. After getting the two to a hospital, Mato and Yomi attempt to track down Saya. Saya, try as she might, is unable to break free from the virus plaguing her by her lonesome. Mato and Yomi finally find their former counselor, only to get easily taken down. Yomi attempts to sacrifice herself, which fails.
Part 3 (EPS 46-49) has Mato brings Yomi to the hospital, before searching for Saya alone. She eventually finds her and demands an explanation. After no response, the two fight, before Mato notices an injury on the older woman's body. She then notices Saya's symptoms, helping her connect the dots and realize that Saya has a parasite in her. Mato is forced into a losing position, before Saya towers over her, preparing to kill her. Mato's fear and determination conflict with each other, forcing her into her Insane form.
Finale/EP50: Black Rock Shooter
Mato experiences flashbacks from her and Saya's talks, interactions, and fights. She also has some hallucinations on what the fight could result in, as well as what their previous fights could have been like. Mato feels sick to her stomach thinking about it.
Mato and Saya's fight is an extended recreation of their fight from the OVA. Mato is stabbed by Saya's sword, before sucker-punching the older woman several times in the gut. She manages to get her former counselor to cough up the parasite, which Mato immediate sets on fire, destroying it. Saya falls unconscious, while Mato calls for an ambulance.
The five women physically make full recoveries, though it will take time for their emotional and mental scars to heal. Mato still spends time with the family that helped her after she got her own place. She visits her friends often, as well as her hometown.