Mizuki Usami is a passionate member of her school's art club, but the club has a problem—Usami is the only member who takes her craft seriously! The lazy club president constantly sleeps through activities and Collette hasn't regularly attended club activities in quite some time. Uchimaki Subaru, despite being an exceptional artist who could win an award if he tried, is obsessed with drawing the perfect 2D wife. Light-hearted and comedic in tone, Kono Bijutsubu ni wa Mondai ga Aru! follows Usami as she struggles to do art club-like activities, often obstructed by her motley crew of good-for-nothings and her distracting crush on Subaru.

Is asking an A Type for cold medicine the best on sick days? What does a B Type wish for on New Year's? Can an AB Type really outsmart a demon? What are O Types like when they end up in the hospital? Which type has the best plan for the dreaded "Valentine's Day and White Day at the office" scenario? Find out the answers to these typical situations and more in the fourth season of Ketsuekigata-kun!

Takuya Arima is a young student whose father, a historian who has conducted various researches, disappeared recently. During a summer vacation Takuya receives a peculiar package from his missing father, along with a letter containing information about the existence of various parallel worlds. At first Takuya doesn't take it seriously, but soon he realizes that he possesses a device that allows him to travel to alternate dimensions. Is his father alive, after all? If so, where is he? (Source: VNDB)

Kaori Sasaki—a member of Uchihama Academy's Astronomy Club—confesses to Sou Akiyama, but later that evening, she dies in a tragic road accident. Her friends and fellow club members mourn her death in a local hospital. Yet she shows up to school the following day, and no one senses anything amiss. The day finishes without any unusual incidents, and the group of friends plans for the upcoming cultural festival. Suddenly, the room is shaken by an unnatural earthquake. Everyone splits up to investigate—except for Nagisa Hanamiya, who stays behind. As everyone leaves, Nagisa notices that the odd relic-like cube that she was toying with starts emitting a strange blue light. Meanwhile, Sou stumbles upon an unconscious, naked girl lying in a pool of water. Ushinawareta Mirai wo Motomete follows the Astronomy Club's increasingly bizarre adventures—from dealing with ghosts to quelling unrests between student clubs. All the while, they unravel the circumstances behind the sudden appearance of a new transfer student.