Who's Texting Young-Ok in "Our Blues"? 3 Convincing Theories

Young-Ok opens up to Jeong-Jun about her last boyfriend before coming to Jeju two years ago. Named Choi Seong-Ju, the two met while working together at a handmade shoe factory in Cheongju. According to Young-Ok, Seong-Jun is a successful shoemaker whom Young-Ok assisted. While the exact details of their split haven't been revealed yet, Young-Ok implies it wasn't necessarily a clean break when she gets worked up talking about her ex's asinine excuse to break up with his previous partners in episode six. There's a possibility that Young-Ok launched into that rant because she's still upset over Seong-Jun's inability to leave her alone following their breakup.