My Unexpected Marriage (Ratshu)

Laritte Brumayer, the illegitimate daughter of a count grew up in an abusive household. As if that wasn't enough, she's sent to marry Duke Ian Reinhardt after he was killed and named a traitor, instead of her sister. Despite her dreary prospects of being a dead man's wife, Laritte is ecstatic to escape and start her new life! Just as she's settling in, Ian returns, claiming he was framed. Though wary of him at first, she agrees to help clear his name, oblivious to the hardships that lie ahead... (Source: Tapas)