It took time for Eunji to process everything from Nathan's confession.
She felt really bad for Nathan. He was being forced by the unfavorable situation he was in.
To put it bluntly, he was also a victim as he was being used by someone who had a malicious intention against her sister, her and her family in general
There's no other explanation but only that.
He was not really innocent but it was not entirely his fault, too.
His and her past were almost the same.
"Did you know why that man wanted my sister dead?" She asked after she had calmed down a little. But still she kept her distance from Nathan.
"I didn't got the chance to find out. As much I wanted to, the international prison was a place that was far from my reach. Even the king had little power in there." He honestly said.