Same author wrote both. They both are lesbian romance but they also have darker elements and some heavy drama. They are both from gmmtv.

Both have Lesbian romance, they are both in the gl genre. They both have a combination of gl romance and a mystery, investigation of murder/death.

Both are set in a similar time period. Both have a lesbian relationship in them although in Couple of Mirrors it has been censored, but a lot of their relationship still remains. Both have a strong female lead that goes against tradition.

Both are a lesbian romance. Both have a lead that is a Princess who falls in love with a woman in a historical setting. social rank and tradition bars the love between two women.

Both have a same-sex romance, manner of death is a bl, Petrichor is a gl. Both have the same screenwriter. One of the leads in both series is a doctor. Both series are about investigation of death/murder combined with some romance.

Both are a lesbian romance. Both have the same actors. Both deal with the relationship of a woman that is a "commoner" and a woman from a rich/royal family. Both have a forced marriage to a man. Both have a happy ending.