Toaru Majutsu no Index SP contains several short story arcs not covered from Index and Railgun's main stories, and adds more insights into the Toaru universe. The 4 stories focus on Stiyl Magnus, Mark Space, Kamijou Touma, and Uiharu Kazari respectively.

A vast kingdom called Lucifenia, whose popular name was the "Kingdom of Yellow," was ruled by a tyrannical fourteen year-old princess named Riliane. Under her absolute monarchism, everything was exploited from people and the ones who did not obey her were executed without mercy. Allen, a servant who looked a lot like her, was always beside the princess whom Lucifenia's people called the "Daughter of Evil." The princess and the servant were the same age, since the two of them were actually twins who were separated shortly after their birth, with Riliane taking her mother's position as the country's ruler and Allen works in the palace as a servant since he was given up for adoption. The princess's selfishness and jealousy caused a war and many deaths, and their secret clockwork of fate was going to spin madly. (Source: Vocaloid Wikia)

A vast kingdom called Lucifenia, whose popular name was the "Kingdom of Yellow", was ruled by a tyrannical princess named Rillianne and she was still only fourteen years old. Under her absolute monarchism, everything was exploited from people and the ones who did not obey her were executed without mercy. Allen, a servant who looked like her, was always beside the princess who was called "Daughter of Evil" by the people. The princess's selfishness caused a war and many deaths, and thus the secret clockwork of fate was going to spin madly. (Source: Wikipedia)

Toaru Kagaku no Railgun: Arts and Sciences City SS is a short story in Arts and Sciences City that takes place in the time period between September 3rd to 10th. Academy City has a exchange program with the rest of the world that allows some students to travel for this week to other places, and some students are allowed into Academy City during this time. Mikoto, Kuroko, Saten and Uiharu went to the Arts and Sciences City, made on a artificial island off the coast of California for a field trip. The Arts and Sciences City is known as a city that has cutting edge technology (in terms of the standards of the 'Outside' of Academy City - ie it is still far behind that of Academy City's), and is trying to take over Hollywood as the entertainment capital of the world. Stuntsmen and shows occur frequently at this city, and anything out of the ordinary is treated as another show. Due to the climate apart from sleeping everyone wears their swimsuits all the time. (Source: Toaru Majutsu no Index Wiki)

Tsubaki, who places an importance of "being cute", picks up a strange fluffy creature and brings it home with her. She brings it into the bath with and it transformed into a naked boy?! What is going on? Is Tsubaki going to live with "Fuwa" (as in Fluffy) the alien boy?!

A jungle and war victims: these fragments constitute You Mizunashi's leftover memories. A doctor's son, You questions whether these pieces of his "past" aren't just constructs of a delusional mind. He forces himself to remember and in seeking his personal truth, alienates himself from his peers and presents school bullies with an easy target. One day, while he is being harassed, a mysterious man—with a gaping wound on his abdomen—appears before You and his tormentors. You hastens to help the stranger and in return, learns that his unexpected patient goes simply by the name "R" and that R trades in secrets.

The distortion of space-time and the song that amplifies it. The distortion of the world amplified by the song, the tone of which echoes in time with the sound of music. This is a tapestry of sad but beautiful sounds spun by the beautiful space-time god Lagthorin, who tries to stop the collapse of the world while bobbing between these distortions, and Merlin, a trickster who has been tailored for the said collapse. (Source: Hakusensha, translated)

Ootsuki, the foreman of the underground debt-slave labor camp, is finally using his one-day vacation above ground. The blacksuits of the Teiai Corporation follow him to make sure he doesn't escape, but are constantly baffled by the completely mundane ways he decides to use his time.

Nayu, a one-in-10,000 magic prodigy, has run out of mana! Now all the antics she got away with because of her magical skill are coming back to hit her like a boomerang… Until she runs into her old student Komugi, the only one who treats Nayu like a normal person. This is a boomerang love-comedy of karmic retribution about a witch who has become painfully useless after exhausting her magical powers. (Source: Sunday Webry, translated) *Notes: \- Originally self-published as a Twitter comic, it was picked up for serialization on Sunday Webry starting 2022-10-28. \- Includes one extra chapter.*

Book one of the *Aku no Taizai* series. Duke Sateriasis Venomania, who, in his childhood, had been mocked and taunted by others. In adulthood, he made a deal with the devil to have an irresistible charisma to women. As a result, women began flocking to his mansion's basement to create a harem for him. One of these women happened to be the one who "made him for a fool." This girl, now a young woman, was his childhood friend, Gumina Glassred.

Six years ago, following a crushing defeat, a group of friends promised that they will one day take their friend Suzuo to the Koshien. Now in their first year of high school, the friends have reunited behind the pitcher Kitaro Kitaoji to keep their promise. With Suzuo as their manager and Kitaro's signature left-handed, underhand "Submarine Pitch," they may just go all the way.

This is the story of five students who make up a crazy and unique group (the gang of the funny faces) and, in an incredible twist of luck, they befriend the cutest girl in school. Of course, they will enter into competition with many groups in their school, where teachers are tricky and sometimes clueless, where they can still defy the laws of nature to win sports tournaments and where you can still be childish, Anything could happen in this high school. (Source: Anime News Network)