I've focused mainly on demon study and research. I do the minimum work I can to keep my former seigneur at bay, and I task an ugly brute demon with working the fields under cover of darkness.
Daytime is only a distraction; you live only for the time when you can covertly delve into the forbidden lore of demonology. You task your demon with doing the outdoors work in your stead, in the dark of night, to avoid getting fired, while you devote all your time to research.
Monsieur Mauriceau has not been pleased to see you slacking, however.
"Don't you have anything to say?" Mauriceau demands.
There are a few ways you could approach dealing with this haughty aristocrat.
You could have your newly bound demon boost your fighting skills, then challenge Mauriceau to a fight here and now, making use of your inhumanly enhanced strength and agility to show him up. You could incarnate your creature as a large, towering figure, aiming to scare him off. Or, to take a more subtle approach, you could target his mind, with strange and disturbing sounds and flashing lights dancing at the edge of his perception.