Pin: Stupid because she can't overcome her conditioning to be loyal to Nai's family, who she has served from childhood. Makes really bad choices as a result. When she does try to protect Yai, it is in the worst possible ways.

Yai: Stupid because he expects Pin to love him and trust him when he has done almost nothing but lie to her and threaten her. Does not support her, but constantly tests her faith in him.

Pin & Yai: They don't talk to each other. They could have told each other what they were doing and why. But they were both lying to each other all the time. It was super annoying.

I'd give all that stupidity a bit of a pass if other bits of the plot were being resolved, but at episode 12 they still haven't done much with any of the major reasons why Yai returned: saving the farm, finding Nai guilty of wrong doings, clearing Yai's name, finding out how his dad died, etc. So at this point, I just have to drop it.

There was no rape, but my husband walked in during the scene where Yai angrily chases her around the room and grabs her by the ankle to drag her across the bed. He said, "Is he going to rape her?" So, yeah, Pin had reasons to be afraid of Yai, I don't care how many commenters want to call him a loveable kitten. If, like Pin and my husband, you haven't gotten to see all his other scenes, he is legit scary.

Most interesting part about the show for me was the theme on how the serving class attitudes of loyalty are detrimental to family life. I have a lengthy comment about it in the comments section if you are interested!