He was just being kind to Yeonwoo because he pitied him.
Yeonwoo was running away while pregnant and when Dane showed interest was when he got sick (same reason he adopted Darling).
But Yeonwoo is cute: Josh thought he might have liked to fuck him if they weren't both omegas.
I suppose Dane might have thought something similar, but, again, Yeonwoo was pregnant and living in his house and Dane prefers shallow one night stands.

Dane is now my favorite. like, literally the most attractive I've seen. dark, buff, and red hair, He's going to be my bias for a good long while I think lol. I just hope he maintains his stoic persona. I've read Kiss me Liar, did he have a thing for Yeonhoo before? cuz it seems like they hinted it. Also, is there a novel that I can read?