Even though at first glance they don't seem to have anything in common it's the atmosphere and the overall feel of the romance. In both shows the affections and bickerings between ML and FL are similarly adorable, feverish, loud, heartwarming, sad, joyous, melodramatic, hurtful, amusing, ...
They take you for an emotional ride and you become very invested in the relationships. Also in those of the supporting casts.
In Lucky Romance the fl is convinced she brings bad luck to people and wants to stay away from others/the people she cares about as a result.
In I'm not a Robot the ml believes he is allergic to people and has built his entire life around never touching another human being.
Though these are obviously different, I found the concepts similar and the general feeling when watching was also quite alike. Both romances are very cutesy and brings a smile to your face.
It is not so much the storyline, but the music that overlaps. The music "written" in the storyline of "The liar and his lover" is even played by street musicians in "I am not a robot". It is probably the only overlapping song, since TLAHL is a music focussed drama and IANAR only has background music, but maybe it is the production, too, I just think, if you liked the one, you might like the other, too. Give it a try.
Both MLs suffer from a strange skin allergy when they touch people but they are mysteriously immune to the FL who then tries to help them.
Well, both have the AI theme. About robots and romance. Just that in "I'm not a robot" FL is pretending to be one (replaces the actual robot) while in "AI Romantic" the FL is the actual robot. :) Both are funny and slightly fluffy. ~