Fumizuki Academy isn't a typical Japanese high school. This unique institution has implemented a new and innovative system to sort its students. At the end of their freshman year, students take a test that divides up the student body. The highest scorers are placed into A class, all the way down until F class, for the lowest of the low. Unfortunately for Akihisa Yoshii, his supposedly "great" intellect wasn't quite enough for such a test, and he's now stuck at the bottom of F class. Naturally, F class has the worst facilities: not only rotten tatami mats and broken tables, but also outdated equipment and worn out furniture. On the bright side, his friend Yuuji Sakamoto is in the same class, and to everyone's surprise, the genius girl Mizuki Himeji has also ended up in the same class due to an unforeseen fever on the day of the test. Unsatisfied with their perquisites, F class rallies behind Yuuji, determined to take on the higher-tiered classes in order to seize their perks by using the school's Examinations Summon Battle system. The participants can summon fantasy characters—whose power levels are equal to their student's test scores—in an all-out battle. Will F class be able to rise to the top, or will they live up to everyone's expectations and fail? [Written by MAL Rewrite]

Akebi Komichi lives out in the countryside with her family. She's won entrance to the prestigious Roubai Academy middle school for girls and now she wants only two things—to wear the school's sailor uniform and to make a hundred friends!

On the 20th floor of the Tower, the "Regulars" who have been permitted to enter have to undertake arduous and extremely expensive tests to rank up. Most abandon hope and choose to stay where they are—but not Ja Wangnan. Wangnan is determined to reach the top and become the king of the Tower. However, he is weak and has repeatedly failed the exam, with debt collectors tailing him. In desperation, he attempts the exam one more time, only to encounter a mysterious and powerful individual: Jyu Viole Grace, a member of the crime syndicate FUG. Cursing his rotten luck, Wangnan has no choice but to form alliances with strong people, including Viole—who still refuses to be part of any team. Amid a dire situation, Wangnan must find a way to change Viole's mind to finally advance past the 20th floor, or he will never get a chance to build his legacy.

Even though Sasaki's droll corporate life is constantly filled with work, it leaves him tired and unfulfilled at the end of every day. In search of some companionship to fill the emptiness in his life, he visits a pet shop on a whim, not realizing he's about to change his life forever. After settling on an adorable bird and bringing it home...his new roommate reveals that it's actually an incredible sage from another world who promptly bestows Sasaki with supernatural powers as well as the ability to cross between worlds. All Sasaki wants to do is use these newfound powers to live in peace and comfort, but there are more than a few colorful characters who might get in the way of that...