After discovering that his orphanage was on the brink of closing due to financial stress, Finn, who was living freely on the streets, set out for a casino with the aim of making a fortune. However, nothing could have prepared Finn for the nightmare that was awaiting him. Once there, Finn encountered a car chase and bloody shootout caused by a man's "lucky" card. Finn will eventually learn what the shootout was about. The world order can be controlled by a set of 52 X-Playing cards with the power to bestow different superhuman powers and abilities to the ones that possess them. With these cards, people can access the hidden power of the "buddy" that can be found within themselves. There is a secret group of players called High Card, who have been directly ordered by the king of Fourland to collect the cards that have been scattered throughout the kingdom while moonlighting as employees of the luxury carmaker Pinochle. Scouted to become the group's fifth member, Finn soon joins the players on a dangerous mission to find these cards. "All you need in life are manners, dignity, and the will to bet on your own life." However, Who's Who, the rival car maker obsessed with defeating Pinochle, and the Klondikes, the infamous Mafia family, stand in the way of the gang. A frenzied battle amongst these card-obsessed players, fueled by justice, desire, and revenge, is about to begin! Are you ready? It's Showdown!!

Self-professed "home security guard" Mahiro Oyama has not left his home in years, secluding himself in his room playing erotic visual novels. This depraved lifestyle causes his prodigious sister, Mihari, to worry about his well-being. In hopes of solving this problem, she devises a plan to rehabilitate him back to normalcy. The first part of Mihari's plan is to concoct a medicine that changes her brother's biological constitution into a bona fide female, much to Mahiro's vehement dismay. Stuck in this predicament, Mahiro has no choice but to live out his life as a cute girl until the effect wears off—if it ever does.

In the near future when technology has significantly advanced, a famous AI TV fortune teller seemingly foresees high school student Asahi Kashiwagi's day with pinpoint accuracy. On his way to school, he encounters Aoi Izumisawa, Bai Mongfa, Karin Istel, Amelia Irving, and Ilya Ilyukhin. Despite meeting them for the first time, Asahi suddenly receives love confessions from all of them at the end of the same day, perfectly aligning with the fortune teller's prediction. As if that was not enough, Asahi soon learns that these five individuals are actually candidates to become his bride, and they have been invited by his father to live at Asahi's home. Left with no other choice, he reluctantly allows them to stay, resulting in a bawdy turn of events that brightens up his average high school life. However, as Asahi spends more time with them, forgotten memories gradually resurface. While uncovering the hidden truth, Asahi begins to believe that his fate with these potential partners might be more than just mere coincidence.

Akira Kiyose, a high schooler who loves to sing, gets recruited by a talent agency called sMiLea Production. Akira learns that the legendary idols "Anela," who shocked the world with their sudden retirement, are behind the agency developing talent. Together with Banri Naoe and Chihiro Isuzugawa, also recruited by the agency, they form an idol group as they chase their dream towards super stardom alongside other idol groups "LEGIT" and "JAXX/JAXX."