Responses
I think when Nanjo asked Pinky "if he stops seeing seonhwa will he also stop seeing him?" I think that was the time he is starting the have mixed feelings for him plus their first "date".
With Nanjo's personality, he's definitely feeling guilty towards seonhwa and couldn't probably sleep with him when he's sleeping with pinky. but I'm 100% sure in season 2 that Pinky will definitely have to step up his game since his blackmail material is over.
Remember in the last chapter is known that nanjo doesn't get hard with seonhwa?? - could it be thats already happening in ch 22 and nanjo just had an erection when Mok leans on his shoulder-- and thats what he refers to when he said "and this might not either" as him having a hard on because of Mok
°°°°°°°°
Aaaaand when mok is sniffing him we have a close up were we can see a little pink on Nanjo's cheek, or im just crazy and it's just a shadow, otherwise nanjo's blushing because of Mok's actions and being turn on
°°°
Just My theories people