You can see it from Taeyeoung. One of his sexual encounters before Jinwoo has BDSM gear on. And then near the end (29/30 chapters) he talks about how far can he push him, how much can he break him in. Then the image of Jinwoo in cuffs with the claps on his nipples. The choking while saying ‘how far before he runs away?’ And making him call him master. It’s definitely headed to a BDSM direction

I’m loving the slow build up of BDSM in this, I didn’t know that was in this and man am I loving it!!!!