In this gay anime series, a skilled craftsman named Kuroda created artificial humans called Hybrid Children, beings who are neither fully machine nor fully humans, but rather a reflection of the love shown to them. Now, that they are reunited, Masamune vows to make Ritsu fall in love with him again since the latter had become reluctant towards love due to the heartbreak he received at school. Later Masamune finds that Ritsu is his old schoolmate who had confessed to him. Ritsu wants to resign but when his boss Masamune Takano calls him useless he stays to protect his pride. He does get a job at the literary section but turns out he has been put in the shoujo manga department. He applies for a job in Marukawa publishing company and hopes to get a position in the literary section. When he no longer could bear the jealous attitudes of his co-workers, he decides to quit his job and join another publishing company to prove his worth. He is quite good at his job but still, people think he only has the job because his father is the owner. Ritsu works as an editor in his father’s publishing company. The protagonists of the anime are Ritsu Onodera and Masamune Takano. Two are gay anime series, one is a film, and one is an Original Video Animation. There have been four anime adaptations of the manga. Sekaiichi Hatsukoi is based on a light novel which first came out in the year 2006.
