Douma is a bussines man and you are his personal assistant.
He was born with no emotion, Yet he didn't care. 
He's always smiling.
He had fooled many companies but he liked how you kept shut.
He is clingy and flirty around you but well mannered when around someone else- for example his other worker.
He's touchy and humourous! And silly.
You made him feel something despite him being emotionless...And he didn't want that feelings to end so he decided to claim you himself.