Magia Record Story I, the Reincarnated Overlord, Magnificently Thwart "THEIR" Conspiracy!!

The following is a summary posted on 4chan's /pmmm/ general.

Simply put, Rui Mizuki ropes in Seira Mihono to Comiket in Kamihama. They become close friends after knowing that they are both magical girls, and also because Seira pretty much accepts Rui's quirky habit of over imagining things. Seira, an inspired movie maker, actually likes Rui's ideas as well.

Being a first-timer, Rui guides Seira through the stalls having a great time even though Rui's favorite artist is absent, sparking her first wild imagination that it is an attack from an evil organization. (Interestingly, Rui actually stopped a terrorist attack at her school by taking down the armed suspect).

Of course, the girls tending the stall inform Rui that the mangaka overslept and nothing is wrong. There is a problem of some dude using fake money though, and the stalls that were victimized make up the chemical formula for Lysine which Rui identifies at a flash, sparking her second imagination that it is a terrorist attack. Of course, there is nothing, though Seira is impressed with how Rui can think up interesting scripts at one go.

However, Rui is still uneasy, and after some gentle prodding, she revealed that she felt someone watching her with hatred way back when they took a photo with the girls tending the stall of her favorite mangaka. Just to be sure nothing is wrong, Rui uses her innate which can see how close people are to death at the girls at the stall and is relief that they are safe. So she and Seira enjoy the rest of their time, especially more since the guy using fake money has been caught.

However, Rui did not turn off her innate, and saw that she is close to death via reflecting from her laptop as she prepares to install her newly bought game. After logical deduction, Seira and Rui return back to the stall since they believe that the hate is aimed at the mangaka and his fans. The friendly mangaka arrives finally, and Rui notes that he is reeking doom.

Just then, a popular mangaka who can set his stall in front of the shutter greets Rui's favorite managaka, and she noticed that he has been the one she knocked into earlier today and seems to hold a sharp object. Despite the stall girls and her fave mangaka explaining he is a close friend, she calls out that he is attempting to harm people.

The guy admits it outright, but he corrected Rui that he is not using a knife, but a gun made from a 3D printer inside the hall since security is pretty tight and thorough for the event.

His reasons was because his favorite character is revealed to have a boyfriend in an ending and thus wants revenge on her creator. Rui manages to stop his actions by showing him the secret ending where it is revealed that this is a facade as the girl is doing this to save the main character. The guy drops the gun and is promptly arrested.

Seira berates Rui for her reckless actions, but Rui explained that the 3d printed gun has lousy accuracy, so the guy will shoot the chest as his best shot, and she already has hid the thick Comiket catalog under her blouse and reinforce it with magic. Even if it is not enough, the chainmail that she wears normally under her uniform and reinforced with magic will do the job. Seira pretends that she doesn't hear that, but did tell Rui that she had a great time and looks forward to participating again.