I'm looking for romance dramas where the ML and FL are left alone to themselves. This means:

No 2ML / 2FL trying to poke their nose in leads relationship.

No mother in law torturing the FL to such an extent that the devil himself will take notes from her.

The exes never come back

No love triangle, square, rectangle, pentagon, hexagon or any other polygon.

I just want the leads to face thick and thin together and figure things out for themselves.

Language preference: Korean>Japanese>Chinese 

Thanks in advance.

Descendants of the Sun 

Devilish Joy 

Goblin 

It's Okay, That's Love this one is really about figuring sh*t out together. 

The Happy Loner 

Honorable mentions:

Weightlifting Fairy Kim Bok Joo at the beginning she has a crush on someone else, and he's finishing off a breakup. No interference from any of those people though.

The Beauty Inside  this definitely have wannabe annoying MIL but I loved the way none of them cared about what she had to say, as should any independent adult. I highly recommend this.

It's hard to find such a drama, where there is no one with crush on leads. But some are at least bearable.

I'm Not a Robot - here are exes, but when they want to come back, they are rejected fast and leads spend most of the time together without anyone interfering. Other characters are just supporting.
Shanai Marriage Honey - leads are practically together all the time. One of coworkers have crush on FL, but it is nothing significant and he is also rejected fast.
Hello, the Sharpshooter - ML and FL have complicated relationship with traumas, which need to be healed. There is almost no one, who wants to interfere or they are dealt with pretty fast. Many people try to help their relationship, not to brake them. It is long drama, but their love is beautiful + there is 2nd couple.
Neechan no Koibito - mature characters and honest conversations between FL and ML.
Sweet Teeth - multiple couples, who are friends - so I think, that there were no triangles, because everyone had their own loves.
My Little Happiness - No triangles with main leads. There are some side characters, who have crush on them, but they are not significant and do not interfere. There is only love triangle with SML's ex, but not main leads.

I know it's hard. I recently finished a couple of Chinese dramas where the sfl acted as if she was born with unlimited access to the ml. She would bully her to great lengths only for everything to be resolved within 5 minutes in the 39th episode and now suddenly everybody are best friends. It  got on my nerves to such an extent that I immediately came here for help.

Anyways thanks for your recommendations. I have watched a few of them, but I'll check out the others