Eriko Hino serves as a waitress at the bar Alexander, working alongside colleagues and friends Kinako Mochizuki and Hiyoko Tamaizumi. During her shifts, she greets customers with a consistently friendly smile and welcoming demeanor. Physically, she possesses yellow/blonde hair, brown eyes, and stands 1.64 meters tall. Eriko exhibits a direct and unfiltered personality, speaking her mind bluntly without regard for others' feelings; she prioritizes honesty and self-consistency over popularity. This bluntness manifests strongly in her intense dislike for Shuusuke Chitose, whom she openly wishes to eject from Alexander whenever he enters. Conversely, she harbors significant admiration for Kakeru Ohtori, overlooking his dismissive or derogatory remarks. Her interactions with Alexander's bartender and owner, Karuo Karube, remain largely unaffected by his often inappropriate comments, which she typically ignores or responds to with laughter due to her strong-willed nature. Eriko also self-describes as a "party wrecker," a reputation that led to her ceasing to receive invitations.