Fourth season of Strike the Blood.

Kohachi Inugami, a detective who specializes in the occult, arrives at a remote village in the Japanese countryside, tasked by a hostess at a local inn to investigate a string of incidents involving rotting and mutilated livestock corpses that have been appearing for seemingly no reason. While surveying, Inugami notices a peculiar young boy working in the fields. Evaded by his peers and called "Dorotabou" for his stench, the young farmhand is surprised that anybody would take an interest in him. Inugami, piqued with curiosity, enlists Dorotabou in helping him with the investigation, despite scorned looks from the villagers. Unbeknownst to Dorotabou, this investigation will reveal a strange new world to him—one of the beast-like entities known as Kemono existing in tandem with humans—along with breathing new purpose into his previously empty life. [Written by MAL Rewrite]

Fumiya Tomozaki is Japan's best player in the online game Attack Families, commonly known as "Tackfam." Despite holding such a revered title, a lack of social skills and amiability causes him to fall short in his everyday high school life. Failing to have any friends, he blames the convoluted mechanics and unfair rules of life, forcing him to give up and proclaim himself a bottom-tier character in this "game." After a fateful meeting with another top-tier Tackfam player, Fumiya is shocked to discover the player's true identity—Aoi Hinami, a popular, smart, and sociable classmate who is the complete opposite of himself. Aoi, surprised at how inept Fumiya is at everything besides Tackfam, decides to assist him in succeeding in what she calls the greatest game of them all. Through the gruesome ordeals of social interactions and relationships, Fumiya begins to advance tiers in the glorious game of life. [Written by MAL Rewrite]

Miki Koishikawa is a high school student who enjoys a very simple life. However, her ordinary life is about to be turned upside down, and she may not be able to handle everything that is coming her way. After a very "fun" holiday in Hawaii, her parents have decided to get a divorce. As if this wasn’t enough of a shock for the poor girl, she also discovers that they will soon be re-marrying and swapping partners with another couple who they met on holiday. In order to include Miki in this shocking turn of events, they ask her to give the new couple a chance, and set up a dinner date with everyone. Miki may have tried to be emotionally prepared for her new parents, but what she was not expecting was their handsome son Matsuura Yuu. Miki develops an instant crush for Yuu. What starts off as a lovely friendship between them soon develops into romantic feelings which they are both finding hard to control. But more trouble is ahead in their relationship, as both Miki and Yuu have admirers of their own who are trying very hard to keep them separated.