Ji-Won was willing to sacrifice himself, so that Su-Jin wouldn't have to walk under those terrible weather conditions. It was his way of atoning for something he considered to be his fault.
Meanwhile, Su-Jin was worried about Ji-Won's well-being.
Even though it was a short ride back to the village, with Ji-Won's special conditions, he would have an awful time before they were able to reach the station. He would be lucky if everything ended with just a palpitating heart and slight shortness of breath. Worst case scenario, he could have a full blown panic attack and even lose consciousness. It even happened with Seo-Jun standing at the wheel, let alone with a stranger.
She wanted to continue opposing such a mad idea, but Ji-Won didn't give her the chance.
After giving Su-Jin a small smile, Ji-Won opened the door and stepped outside.
