I can't really comment for other people, but personally, I was kind of expecting the possibility of the rape scene just as you did. However, there was a part of me that was thinking that maybe the author would withhold any intimacy between the main characters until such time that Seungho has shirked off a considerable amount of his malice and has grown to genuinely care for Na-Kyum. But alas, it happened while he was still a dick, and I had to live through the rape scene like everyone else.
I signed myself up for reading this story for its plot, beautiful art, and the time period it is set. So despite the drama of their first intimate encounter, I will see it to the end. Quietly.
I don't get it. Did people not think the plot would lead to rape? I saw it coming a mile away. ┑(￣Д ￣)┍
Stop lying to yourselves, you all saw it coming and continued to read this series anyway you snowflakes!