When It Rains, It Pours

Both are Japanese BLs with a cheating plot (while initially in an unhappy relationship) and the development of the physical and romantic relationship between the 2 main leads that is complicated.

Both Japanese BL dramas are a controversial in subject matter with a complex relationship between the 2 main characters that encounter obstacles of others (past/present partners) to their relationship.

If you like the trope of people getting to know each other online and the big reveal of their real identites being someone already close to them. This one is a Japanese BL.

Similar vibe and cinematography. The dialogue is slow and intentional. The story is sweet but heartbreaking.

Both are BL dramas with a relationship between the 2 main characters that isn't the most conventional. Both have rain as a motif in the series.

Both are BL dramas with characters that are red flags, and have jealousy, obsession, manipulation and control. The main character is stuck in a love triange (or square). In Futtara Doshaburi, the MC has 2 guys fighting for him while in Secret Relationships there are 3.

Dramas share the same director, there is similarity in cinematography and pace. Both are bl, however plots differ a lot., those are about romance development

Beside that both Therapy Game and When It Rains, It Pours are J-bl, they're about a chance encounter between a straight man and gay man. As both series progress, the relationship develops from friends to lovers. I'm drawn to the idea of a straight man's pov. What makes a him fall for a gay man? Or perhaps I am intrigued by how the gay person seduce the straight man!?

Both are japanese dramas that center on a complicated situationship mostly and initially motivated by sexual desire/loneliness. The characters' meeting is a coincidence but the characters realise they have much more in common them they thought. Both are also romantically entangled with/romantically interested in other people.
Lgbtq+ characters and content too

Not similar in story but in some themes and the feel.

Both have two people living together in an apartment, trying to manage their relationship with some complex elements. If you like one you might like the other.

both have tensions and struggles between the MLs and the overall feel is similar.

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Another angsty Japanese BL drama where the couple finds their way to each other after parting ways.