I didn't quite understand this scene. They were married, they had a house, so why have sex in a car? Can anyone explain?

I was confused too, but maybe was something related to the routine and stuff.

@theburbs said:

I didn't quite understand this scene. They were married, they had a house, so why have sex in a car? Can anyone explain?

I guess house is small so they want to have some privacy, it's quite common in Japan too for people to go to sex hotels just for hour to enjoy privacy compared their small apartments if shared with children or someone.