Hajime Tachibana is a supporting character in the anime Yume Tsukai, who serves as one of the Dream Messengers, a group tasked with resolving supernatural incidents caused by dreams spilling into reality. At twenty-nine years old, he is one of the older members of the team and is assigned the name Friday, with his specific role being the dream apostle of Friday Castle. While possessing conventionally handsome features, his unusual personal sense of style and fashion are notable for being far outside normal standards, though this eccentricity serves a specific purpose.

Tachibana's most defining characteristic is his extreme and unrepentant preference for young girls, specifically those aged twelve and under. He operates under a rigid and highly unconventional personal classification system where females aged thirteen or older are dismissed as middle-aged, a woman in her twenties is considered a grandmother, thirty-somethings are fossils, and anyone over forty is referred to as an existence predating the creation of the universe. This worldview shapes his every interaction, as he considers younger girls to be the only ones worthy of his attention and interest. His choice of distinctive clothing is deliberately intended to attract the interest of girls in this specific age demographic, and he becomes annoyed when women outside of this group approach him while he is wearing normal clothes.

Within the group, Tachibana’s primary target for his affection is Rinko Mishima, the younger sister of the team leader, as she is the only member who fits his narrow criteria of girlhood. However, his persistent flirtations are unwelcome, and Rinko regards him with visible disgust and treats him as a dangerous individual to be avoided. This dynamic forms the core of his interpersonal relationships within the story, positioning him as a problematic and comedic figure whose advances are consistently rejected. Despite this repellent aspect of his personality, he remains a functioning member of the Dream Messengers, contributing to their missions to combat the darkness that arises from human hearts. His motivations revolve around his distorted romantic and aesthetic interests, although he does participate in the group's primary objective of using their powers to bring dreams back under control. As a Dream Messenger, he is presumably capable of using an old spell and a specialized toy to connect the fabulous world with reality and suppress nightmares, though the full extent of his individual abilities is not detailed. Little information is available regarding any significant character development or change in his behavior over the course of the series.