What is this cannibal film?

Ah, so can’t remember what this film was called and don’t know who was in it.....so can anyone enlighten me?
A young man is kept in a cage in a room (think there is some kind of sliding wall), anyway it’s in the lounge. He’s often not hidden away, but they are obviously pros at this game! The couple are older, a husband and wife. Think he got his wife in to it? She seems like the easy target for the man being held as a prisoner. They are keeping the man to eat mature him and then eat him. The husband dies (does the man kill him?) and the wife lets the man out I think, but then the man ends up being trapped again in the cage and having to eat her....and that’s how he’s found in the end.
The film wasn’t gross, it was more of a dark comedy come suspense type thing.
What the heck is this film please?