Recommendations

They are both based on shoujo manga and very similar in the terms of high school love and characters.

they are both the same dramas (obviously) and I really liked it!
(BTW: Do Min June (Kim Soo Hyun) looks so cute! (I wish he's my husband!!!!!)

Both of them are full of sweetness and sadness and the main actors have the same good chemistry.

Similar situation, a popular actress and a regular guy, and then a love blossoms.

I haven't watched this drama yet but the premise of it seems very similar to the Korean drama, 49 Days, in that a spirit of a person occupies another person's body for a period of 49 days.

Both shows are psychological thrillers where the bad guys want to change a "fallen" Japan by singling out their "chosen ones." Both are more centered upon the mysterious plot than any romantic themes. Part terrorism, part friendship; the stories give a little bit of the same feel. Fallen Angel is shorter though and a little bit less in depth/drawn out.

They are both about traumatized young boys finding brothers to protect and get them through. In RH+, the brothers are adopted and vampires; in Fallen Angel, they are actual kin. But still, the bromance feeling is the same. Both shows are mainly centered around the boys and have supernatural/psychological thriller themes.

both movies are an adaption from mangas and in the action / thriller genre

Music, romance, very sweet characters. Kanojo wa Uso Wo Aishisugiteru is a bit more mature and slightly melodramatic (but only very slightly). Make sure you watch until after the credits ;) while Ai Ore! Is more superficial and scripted to fit the label 'cute' (as with many manga adaptations)

The wife is having an affair and the vibe is the same.both are mature dramas with beautiful acting.

The kings in both dramas are almost or completely (you be the judge) insane.

Contain similarities like going to the past via an unusual time travel method to fix simple moments in a comedic way.

Both have a main character who starts a rock band while trying to get a girl's attention.

Both are about the band's story and both movies are music-themed

Gong Hyo Jin. i've watched two dramas both and i absolutely love her acting and her chemistry with the actors are undeniable ! she's an amazing actress, no doubt. And there are a lot of love scenes in both dramas.