We don't know if they're related but I wouldn't be surprised if they were. And yes I pretty sure he likes Ren, I just dunno if it's necessarily romantic or just familial or as friends
In the novel this was much more terrible, tense and sad... Sung Jin-woo takes a long time to arrive, they fly at full speed, but still, the dragon is not supersonic. Here it looked like he arrived in an instant...
I cried so much that if someone came here when I was reading this manga they would think that someone had died.
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