Kiko-chan's Smile is an anime and manga series about a kindergarten student who has many of the features of a child prodigy but at the same time has many bizarre habits and an odd personailty.

Having resolved the crisis in the Petrification Kingdom, Senkuu and his companions gear up to deal directly with the mastermind behind the petrification phenomenon—who supposedly resides on the moon. The ambitious spaceship project, however, requires immense manpower and critical resources scattered across the world. Thus, the Kingdom of Science exploration team kick-starts its transcontinental journey on the ship Perseus to gather them all. Equipped with modern technology and bolstered by the new, capable members in their ranks, the exploration team feels confident about setting sail to their first destination: America. They soon realize that the region now hosts adversaries controlling the resources they need, doing so with scientific technology which rivals and even exceeds their own. In a battle of science versus science, Senkuu and his team must outsmart their rivals if they are to have any chance of ensuring the continued survival and rejuvenation of humanity.

Saku Chitose appears to lead an enviable high school life. Extraordinarily charismatic, tremendously confident, and effortlessly friendly, he is the kind of person others naturally look up to. But his popularity carries its own burdens; not everyone views him kindly, and whispers of cynicism follow wherever he shines too brightly. To Saku, living an ugly life is worse than death—a belief that drives his need to maintain his perfect reputation. At the start of his second year, Saku's homeroom teacher asks him to help bring back a classmate who has stopped attending school. Initially hoping to resolve the matter quickly, Saku finds out that the shut-in Kenta Yamazaki harbors open contempt for him and everything he represents. A simple favor instead exposes the distance between those who live within the social light and those who were never given a chance to shine. Surrounded by the expectant gazes of those who both admire and despise him, Saku treads the delicate line between sincerity and performance—searching for what it truly means to live beautifully in a world that sees only the surface.

Meisuke Nube Nueno, a teacher at Doumori Elementary School and expert in the occult, finds it increasingly difficult to protect his students against dark forces. After one of his students is sent to a parallel world, Nube encounters an unusual spirit that sends him back in time to change one regretful event. Although Nube manages to fix the situation, this succession of unlikely events suggests that a more serious menace may be threatening the peace of Doumori. To protect everyone he holds dear, Nube will have to overcome the demons of his past and uncover the nature of the looming supernatural danger.