I did not realize filming for the drama was still on-going until I saw the latest instagram updates of their last group photo together. The schedule for drama filming in Korea seems to be really tight most of the time and shooting of the episodes is usually completed close to the broadcast date.
From the above, it looks like the butler couple got married in the end. Though Louis had wondered if he should propose to Bok Sil in tonight’s episode 14, I do not think they are ready for the commitment yet. His character still has a lot of growing up to do.
Some of the media articles mention that the last 2 episodes will be shown together tomorrow night.