Black Diamond

Yuu is a successful and charismatic executive known for his sharp business acumen and social charm, though he behaves like a spoiled child at home. Haunted by a difficult upbringing and a hidden family issue, Yuu relies on his devoted secretary, Asa, who is deeply attached to him but keeps his feelings in check due to his loyalty. When Asa's cunning former university senior reappears in their professional lives, the situation forces both men to confront their histories and the nature of their connection.