ML is a fictional character of the FL's novel/diary in both dramas. One day, the ML arrives in front of the FL and they started to live in the same apartment.
Similarities:
-Both have reincarnated characters and storyline.
-Both have people wanting to be set free and understand what's happening.
-Some comedy and special effects.
Both the Journey and it's sequel are about sci-fi and time travel as well as immortality and different lives. A few people suffer from similar amnesia. And it's a combo of costume and modern drama as well. Also has a love triangle.
Both dramas have MLs that come out of stories to the real world and continue to have an overly romantic and idealized personality and behavior due to the way they were written.
In both drama, the love story the female leads wrote as teenagers occurs in real life. Instead of falling immediately love like the characters they wrote, they only feel unnerved and cringed.
Dear Diary and ZGSSBGXQ both feature ML that resemble one another quite a bit in both looks and personality. The humour is similar at times, even though there is no time travel element in ZGSSBGXQ, the humour is all modern satire.
While there are a lot of differences between the two dramas, the obsessed ML and the overall craziness are very similar. They are both dramas for people who can give themselves over freely to wild and funny plot lines, while leaving reality and logic behind for an hour.
Both started off as a cheesy slapstick fantasy comedy. But somehow along the way, deeper social commentaries came through all their nonsense. Gradually, we started to see them as more than one-dimension characters.