Oh Ha-jun was born in a "golden cradle," the son of a powerful CEO whose every move affects the global cryptocurrency market. Despite his immense wealth, he chooses to work as a mechanic. He is polite and "nice" but possesses a rough edge. He takes Yul-seo on expensive dates and treats her well, but his care is superficial. The controversy of his character is that despite his billions, he allows Yul-seo to continue sex work; he views her as a high-end luxury he enjoys rather than a person he loves enough to "save."