I'm not a robot is about robots, and yet its more like your conventional romantic comedy more than anything else.
The basic premise includes a robot and the female lead impersonating one. Over time, as she falls in love with the male lead, this large secret hangs over their head before misunderstandings com into play. It's the core of most romantic comedies.
The strength of the show comes from the lead actors who manage to play the heartbreak, the cute and the romance amazingly well. In particular Yu Seung Ho successfully carries the role of an isolated male craving to overcome his illness and make human connections. He takes what could be a very childish character and makes you ache with him. Chae Su Bin keeps the cheer up without coming off as overly perky and the rest of the cast is well played as well.
The storyline and directing are serviceable, definitely raised by the great acting.
A definite recommend for fans of romantic comedies, and less so for fans of pure sci-fi.