It is one sided. The ML is in love with his teacher, but she does not have feelings for him.
Yeah, you are right. For the most part the FL sees the ML just as a student even when he isn't a minor anymore. To be honest I wasn't expecting there to be any romantic love in the show at all. I though that the amount of respect and appreciation that was show by their actions proved to be enough platonic love for me.
This was the same question I asked when deciding if I wanted to start this drama. I just finished watching episode 16 about 5 mins ago. I think slight romance is the best way to describe the chemistry between the leads . Since the story is about a student and his teacher the romantic aspect isn't strong in order to maintain ethics. The romance is seen by the actions of the two leads for each other rather than out right spoken "I love you". The plot was strong enough, in my opinion, to keep the watcher happy with the level of romance it contained.
Is the drama really dark? The first 10 minutes gave a very dark almost sky castle meets penthouse vibe. I don't know if i'm ready for that level of darkness.