Oto no Nai Ame wa Furitsuzuku

When Akira and his younger brother's mother suddenly dies, the father they had never known sends his right-hand man, Hyougami to retrieve the two to live with him. Their father turns out to be the chairman of the powerful Kasuga group-a company that rules everything with their influence, including the new life of the brothers. Akira soon finds out his life is being controlled by Hyougami-and Hyougami will use everything in his arsenal to get what he wants.

(Source: Juné)