Why is this so underated????

The story is classic and typical (or not/?/ the premise is kinda similiar to Goblin (korean drama)) but still touching and got me in tears especialy on the last two, with a touch of boys love in it. Character is developed well, there's multiple couple happened here with also some of love triangle and jealousy. There're many conflict happened in every episode so it's not that type of "romance focused" series. They added some trivia of the health condition for the patient. This series is kinda burning, but that's what makes me stick till the end of the series.