I would say rather than similar, they contrast quite a lot. While Moon Lovers has a darker and more complicated plot, Love in the Moonlight is just what you would like to watch after crying because of Episode 20 of Moon Lovers. It will make you smile because of the cute love story, though of course, you will also cry.
Gyun Woo is a college student, more interested in picking up girls, drinking with his buddies and avoiding his nagging mother whenever possible. While riding the subway, a drunken girl then changes his fate forever. She's nearly unconscious on the train and vomits on an older guy. She then leans over to Gyun Woo and everybody assumes she is his girlfriend! Gyun Woo soon finds himself in a relationship he didn't ask for, but soon unable to forget this sassy girl.
f4 (+ previous versions) and moon lovers are my favorite dramas by far. moon lovers is truly a masterpiece, and actually very similar to f4 in my opinion:
- FL is courageous, strong, kind, funny, and stands up to the ML. she really is the ML's ray of light.
- ML is kind of an anti-hero. his mom is VERY similar to thyme's mom, and grew up in a very cold/abusive environment. this causes him to be violent, impulsive, and everyone is scared of him. when he meets the FL his world becomes bright, and he falls heads over heals first. like in f4, the FL is in love with someone else first. the ML kind of bullies/teases the FL before professing his love (that scene still gives me chills)
- ML is persistent, says he'll never let her go, etc.
- there is a reverse-harem-- a bunch of good looking guys who are praised (bc they're the sons of the king)
- overall, the plot is so interesting! the FL travels back to the Goryeo era in ancient Korea. it made me cry so many times, and is by far my favorite drama other than f4/BOF <3.
- FL is courageous, strong, kind, funny, and stands up to the ML. she really is the ML's ray of light.
- ML is kind of an anti-hero. his mom is VERY similar to thyme's mom, and grew up in a very cold/abusive environment. this causes him to be violent, impulsive, and everyone is scared of him. when he meets the FL his world becomes bright, and he falls heads over heals first. like in f4, the FL is in love with someone else first. the ML kind of bullies/teases the FL before professing his love (that scene still gives me chills)
- ML is persistent, says he'll never let her go, etc.
- there is a reverse-harem-- a bunch of good looking guys who are praised (bc they're the sons of the king)
- overall, the plot is so interesting! the FL travels back to the Goryeo era in ancient Korea. it made me cry so many times, and is by far my favorite drama other than f4/BOF <3.