sunny..... okay listen i love that man as much as the next person.... BUT THINKING ABOUT SOMEONE ELSE WHEN YOU HAVE THAT BEAUTIFUL MAN MR.LEE I MEAN COME ON!!!
Maybe it was a flashback because of something Taesung said.
The relationship with Young could've been a bit traumatic for Sunny. Things like that happen often in other manga. So I wouldn't think that Sunny was thinking about sex with Young in a positive way.
i came back to that scene and it wasn't really anything taesung said, it's almost like it came out of the blue. but now that i think about it, you're probably right, young seems to be really manipulative.
I think he is the typical scum seme "manipulative, over possesive, a stalker, is treating the Uke like shit and doesn't want to let him be happy" and all of that without loving his partner.
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eh, sunny suddenly thought of young (also having sex w him) in the middle of sex which kinda killed my mood and made me sad for taesung because that must mean sunny's feelings for young is still there. i hope sunny doesn't hurt taesung.
+ turns out that the absolute dickbag named young already knows that sunny liked taesung back in high school (?) and is asking about him and probably planning to sabotage their relationship.