Everyone in the world uses smartphone apps. But inside them lurks unknown creatures called "Appli Monsters," or "Appmon." The Appmon are AI lifeforms with the ability to think and act, and exist in the boundary between the human world and digital space. In the vast sea of the internet, the "last boss AI" Leviathan takes control of the Appmon with a virus and begins hacking every system, thus starting to control the human world from the world of the net. Haru Shinkai is led to acquire the Appli Drive, and uses it to materialize Gatchmon, a search app monster. (Source: ANN)

Forming a party with one's mother in an online game seems not only unlikely but also uncomfortable to most teenage gamers. Unfortunately, Masato Oosuki finds himself in that exact scenario. After completing a seemingly meaningless survey, he is thrown into the world of a fantasy MMORPG—and his mother Mamako actually tagged along with him! On top of all of that, Mamako turns out to be an overpowered swordswoman, possessing the power of two-hit multi-target attacks! After minor tension between the two, they search for party members, meeting the merchant Porta and the sage Wise, starting their journey to clear the game. [Written by MAL Rewrite]

Dog Days takes place in the world of Flonyard, an alternate Earth inhabited by beings who resemble humans, but also have the ears and tails of specific animals. The Republic of Biscotti, a union of dog-like citizens, has come under attack by the feline forces of the Galette Leo Knights. In an effort to save Biscotti, Princess Millhiore summons a champion from another world in order to defend her people. That champion is Cinque Izumi, a normal junior high student from Earth. Agreeing to assist Biscotti, Cinque retrieves a sacred weapon called the Palladion and prepares for war. In Flonyard, wars are fought with no casualties and are more akin to sports competitions with the goal of raising money for the participating kingdoms. Cinque is successful in his role as Biscotti’s champion, but learns that a summoned champion cannot be returned to their home world. The scientists of Biscotti will endeavor to find a way for Cinque to return home, but until they figure something out, he must serve Princess Millhiore by continuing to fight as Biscotti’s hero.

Cinque returns to the land of Flonyard in Dog Days' to resume his duties as the hero of the Biscotti Republic and it's as though he never left! The difference this time is that he's brought two friends with him who become heroes in their own right: childhood best friend Rebecca Anderson, who becomes the hero for the Principality of Pastillage at the urging of their leader Princess Couvert Eschenbach Pastillage, and his cousin Nanami Takatsuki, who becomes the hero for the Galette Lion Dominion. As with the first season though, with so many secrets to be uncovered and mysteries to be solved, will there even be time for the athletic events that these three hyper and athletic teenagers love to participate in so much?