There needs to be a limit on the Melo.........and unfortunately this script writer didn't get the formula right.
Till episode 12 it w a s tolerable, after that the next 4 episodes just dragged out the brain tumor thing.
It's a k drama for God's sake. It's based on a few people's imagination - so to drag the torturous tragedy of a loved one at the throes of death in an attempt to just fill four hours was very poorly executed.

The FL was also beginning to look exhausted - not from the brain tumor - but this make believe trauma of pretending to be sick for 4 episodes.
By the end of it we wished she had actually died and moved on.

The poor ML struggled to keep the eternal flame of his undying love burning. Every support cast looked fatigued.

Gosh - just change tracks and give another character some misery since that was the underlying theme of this drama.