After taking one hundred secret photos and observing him from afar for months, second-year high schooler Yuki Kurihara has finally mustered up the courage to ask out her first-year crush Shinya "Momo" Momotsuki. Although taken by surprise, the bashful Momo accepts; however, he does not know the profoundly abnormal truth. As her strait-laced friend, Norika Mizuyama, has observed, Yuki has developed some unnerving—but nonetheless sincere—habits: taking pictures of Momo in secret, doing extensive research into his personal life, collecting his used straws, and even going "Momo watching." Though Momo remains blissfully unaware of his new girlfriend's peculiar habits, he does notice some oddities in their daily conversations. Still unsure and nervous about his first relationship, Momo finds himself regularly getting into awkward interactions due to his inexperience, but nevertheless resolves to make his new girlfriend happy. Momokuri follows Yuki and Momo as they shyly explore their newfound love, and also deal with the problems that arise from it. [Written by MAL Rewrite]

Featuring stories from the manga not adapted in the main anime.

Freshman Kaho Nikaidou is from an influential family, and as such, no one has ever said anything even remotely mean to her, for fear of incurring her household's wrath. Wishing to be around people who will not treat her as special because of her background, she leaves home to live at a dormitory for her new school year. Shortly after arriving, Kaho accidentally wanders into traffic and is saved by a tall, handsome stranger. When she asks for his name, he tells her she is weird and walks away. Having finally met the only person to ever say an unkind word to her, Kaho falls head over heels for her savior. After meeting her rescuer yet again and discovering that his name is Kanade Takahashi, she confesses her love to him. Kanade says he would like for them to be a couple, but that Kaho may not want to date him after she finds out his secret. To her shock, Kaho discovers the startling truth: Kanade is a fifth grader! Deciding that she can't date a fifth grader, Kaho intends to break up with him. But as she spends more time with Kanade, she begins to care for him even more and continues dating him. Hatsukoi Monster follows Kaho's first steps into love with Kanade, her immature, yet kind, fifth grade boyfriend.

Suffering from frequent asthma attacks, young Anna Sasaki is quiet, unsociable, and isolated from her peers, causing her foster parent endless worry. Upon recommendation by the doctor, Anna is sent to the countryside, in hope that the cleaner air and more relaxing lifestyle will improve her health and help clear her mind. Engaging in her passion for sketching, Anna spends her summer days living with her aunt and uncle in a small town near the sea.

One day while wandering outside, Anna discovers an abandoned mansion known as the Marsh House. However, she soon finds that the residence isn't as vacant as it appears to be, running into a mysterious girl named Marnie. Marnie's bubbly demeanor slowly begins to draw Anna out of her shell as she returns night after night to meet with her new friend. But it seems there is more to the strange girl than meets the eye—as her time in the town nears its end, Anna begins to discover the truth behind the walls of the Marsh House.

Omoide no Marnie tells the touching story of a young girl's journey through self-discovery and friendship, and the summer that she will remember for the rest of her life.