Invertia was a meteor storm that caused an unprecedented disaster during the 20th century. Because of this disaster, numerous cities around the world were destroyed. However, within the meteor, an unknown element called mana was discovered. It allowed human technology to make rapid strides giving rise to a new species of super-powered humans, the Star Pulse Generation (Genestella). The Festas (Star Warrior Festivals) host battles between Genestella at a city of six academies called “Rikka,” also commonly known as “Asterisk.” Scholarship student Ayato Amagiri transferred into Seidoukan Academy in order to fulfill his own wish, swearing he too will fight in this city.

In the Holy Grail War, seven magi chosen by the Holy Grail itself must summon seven Heroic Spirits to compete for the omnipotent Grail, a magical device that grants the victor any wish they desire. After three inconclusive wars, the fuse has now been lit once again for the fourth time.

A year after the events that took place during the "Final Battle" and equipped with an all-new completed Omnitrix, 16-year-old Ben Tennyson has to face new enemies.

Naota is a normal boy who kills some time with a normal girl by a stream that flows underneath a bridge. Nothing unusual happens in this town. The fact that Haruhara Haruko crashes into the main character with her Vespa a short while later and subsequently hits him over the head with her Rickenbacker 4003 bass guitar doesn’t really make any difference to any other day here. The at first glance unconnected, bizarre events that don’t seem to follow any pattern whatsoever don’t change anything about Naota’s boring life, either – because nothing incredible ever happens in this town.

In a futuristic society, Japan has implemented a complex system referred to as "The Red Threads of Science" to encourage successful marriages and combat increasingly low birthrates. Based on a compatibility calculation, young people at the age of 16 are assigned marriage partners by the government, with severe repercussions awaiting those who disobey the arrangement. For Yukari Nejima, a teen that considers himself average in every way, this system might be his best shot at living a fulfilling life. However, spurred by his infatuation for his classmate and long-time crush, Misaki Takasaki, Yukari defies the system and confesses his love. After some initial reluctance, Misaki reciprocates his feelings in a moment of passion. Unfortunately, before the two can further their relationship, Yukari receives his marriage notice. He is then thrown into a confusing web of love and lies when his less-than-thrilled assigned partner, Ririna Sanada, becomes fascinated with his illicit romance.

Toujou Basara is a high school student whose father has suddenly just remarried. His father then departs overseas leaving Basara with two new beautiful step-sisters. Little does he know, his new sisters, Mio and Maria are actually the new Demon Lord and a succubus!? Almost trapped into a life of servitude, Basara forms a reverse contract by accident and ends up becoming Mio's master! Hijinks ensue as Basara finds himself in one ecchi situation after another. However, Mio's life is in danger as she is pursued by demons and heroes!

Lux, a former prince of an empire named Arcadia that was overthrown via a rebellion five years earlier, accidentally trespasses in a female dormitory's bathing area, sees the kingdom's new princess Lisesharte naked, incurring her wrath. Lisesharte then challenges Lux to a Drag-Ride duel. Drag-Rides are ancient armored mechanical weapons that have been excavated from ruins all around the world. Lux used to be called the strongest Drag-Knight, but now he's known as the "undefeated weakest" Drag-Knight because he will absolutely not attack in battle. After his duel with Lisesharte, Lux ends up attending the female-only academy that trains royals to be Drag-Knights.

OMG! There’s this girl at school, Yamada, who wants to make like a hundred sex friends. She totally thinks she can devirginize one hundred different boys! Can you believe that? That’s like every boy in the school. Who does she think she is? I heard from my friend’s neighbor’s cousin’s lab partner that Yamada’s never even been kissed. Oh. My. God. I would totally die. That’s like burn all your makeup and shave off your eyebrows embarrassing. I can’t even think about it. Today at lunch I saw Yamada flirting, like for reals flirting, with that geek Kosuda. You know the guy. Photography club, no muscles, boring face, kind of reminds you of a black-and-white movie. Super lame. If Yamada can’t even make the sex with him, she’ll never score a hundred cherry boys. She needs to take like Sex Ed or something because I heard she can’t give it away!

The theft of the Greater Grail from Fuyuki City leads to a splintered timeline in which the Great Holy Grail War is waged on an unprecedented scale.

For years, a great war has raged on between the scientifically advanced Empire and a paradise of witches known as the Nebulis Sovereignty. This age-old battle sets the scene for a fateful encounter between two young combatants: an imperial swordsman, Iska, and the witch princess, Aliceliese. As sworn enemies, they vow to cut each other down in order to unite their worlds, and yet Iska finds himself entranced by her beauty and righteousness, while Aliceliese is moved by his strength and resolve. In the midst of a never-ending war that forbids them from being together, they have no choice but to destroy each other-or find another way.

For high school students like Shouichi Kamita, university entrance exams and the future are common concerns. It is also during this time in life that a mysterious emotion that vexes people of all ages may begin to weigh upon one's mind—love. At this point in his teenage years, Shouichi finds three girls he could see himself having a future with: the ever-cheerful Hikari Tsuneki, who teases Shouichi without mercy, but actually has a softer side; the competitive gamer, Tooru Miyamae, who has difficulty communicating with others; and Shouichi's childhood friend, Kyouko Touno, the sometimes immature shoujo manga enthusiast. Seiren follows Shouichi's relationships with these three girls across three separate arcs, as their feelings grow from mutual interest and blossom into something more beautiful.

A new school term begins, as does the season of new encounters. As he surveys his class full of couples, Hashiba Jun'ichi's mind is filled with distress as he asks himself, "Why am I still a virgin?!" Having heard from his friends that the easiest way to fulfill his long-standing desire to graduate from the fellowship of virgins is to kowtow to a gal, Jun'ichi does exactly that and asks his classmate Yukana out. And unbelievably, she actually agrees to date him. What will become of Jun'ichi from now on?

Year 198 of the Solar Era in Tokyo, special fire brigades are fighting against a phenomenon called spontaneous human combustion where humans beings are turned into living infernos called "Infernals". While the Infernals are first generation cases of spontaneous human combustion, later generations possess the ability to manipulate flames while retaining human form. Shinra Kusakabe, a youth who gained the nickname Devil's Footprints for his ability to ignite his feet at will, joins the Special Fire Force Company 8 which composes of other flames users as they work to extinguish any Infernals they encounter. As a faction that is creating Infernals appears, Shira begins to uncover the truth behind a mysterious fire that caused the death of his family twelve years ago.

One day, high-school boy Yamada bumps into the beautiful girl Shiraishi on the stairs (literally), and their lips touch as they fall. When they regain their wits, they realize that they have swapped bodies. As time progresses, the two realize that this is not the only mysterious happening in the school.

Haruka Shinozaki has been interested in the class representative, Akiho Kousaka, since his first year in high school. She is attractive, good at sports, and is an all-around model student. Since they are in the same class this year, Shinozaki decides to confess his feelings—and, to his shock, Kousaka agrees to be his girlfriend! However, he finds that Kousaka is a bit stranger than he first thought: this seemingly perfect girl has never been in a relationship. But even though she is inexperienced, she vows to please Shinozaki in every way she can... such as learning multiple sex positions or his fetishes. Shinozaki tries to assure her that her studies into such subjects aren't necessary, but Kousaka devotes herself to making him happy in more ways than one.

After a traffic accident, Kazuma Sato’s disappointingly brief life was supposed to be over, but he wakes up to see a beautiful girl before him. She claims to be a goddess, Aqua, and asks if he would like to go to another world and bring only one thing with him. Kazuma decides to bring the goddess herself, and they are transported to a fantasy world filled with adventure, ruled by a demon king. Now Kazuma only wants to live in peace, but Aqua wants to solve many of this world’s problems, and the demon king will only turn a blind eye for so long…

High school girl Maika Sakuranomiya has trouble finding a part-time job because of how scary she looks when smiling. However, she is scouted one day by Dino, the manager of the café Stile where its waitresses play unique traits such as tsundere and younger sister. Maika is given a sadist trait because of her looks and has to adopt a dominant and cruel persona when servicing customers, particularly masochist ones.

In Tokyo's downtown district of Ikebukuro, amidst many strange rumors and warnings of anonymous gangs and dangerous occupants, one urban legend stands out above the rest—the existence of a headless "Black Rider" who is said to be seen driving a jet-black motorcycle through the city streets. Mikado Ryuugamine has always longed for the excitement of the city life, and an invitation from a childhood friend convinces him to move to Tokyo. Witnessing the Black Rider on his first day in the city, his wishes already seem to have been granted. But as supernatural events begin to occur, ordinary citizens like himself, along with Ikebukuro's most colorful inhabitants, are mixed up in the commotion breaking out in their city.

Masane Amaha and her daughter Rihoko are on the run from a government child welfare agency that wants to take Rihoko away from her mother. They are caught and Rihoko is taken away. Meanwhile, Masane is attacked by an advanced weapon that can disguise itself as a human being. When faced with the danger, a strange light emits from her wrist and she transforms into a powerful being. She becomes involved in a power struggle between powerful organizations, with her at the center of their attention because she holds the greatest power of them all, the legendary Witchblade.

High school student Chiyo Sakura has a crush on schoolmate Umetarō Nozaki, but when she confesses her love to him, he mistakes her for a fan and gives her an autograph. When she says that she always wants to be with him, he invites her to his house and has her help on some drawings. Chiyo discovers that Nozaki is actually a renowned shōjo manga artist named Sakiko Yumeno. She then agrees to be his assistant in order to get closer to him. As they work on his manga Let's Fall in Love (恋しよっ), they encounter other schoolmates who assist them or serve as inspirations for characters in the stories.