I may be dumb and don't know how to read between the lines, BUT, I'm pretty sure Jin is doing this because he doesn't want to get his hopes up and he probably feels bad for fuc**** with Woo. As we have all seen so far, Woo is naive and pretty gullibe. He doesn't even know what his feelings mean yet. I think Jin knows that if he keeps this up that Woo might become something that he didn't even wan't in the first place. Remember y'all Woo was hard drinking when he realised the person that he has been talking to in the game is a guy. I honestly don't think that Woo has anything agains't gays I also can tell that he is slowly falling in love with Jin. But, this all started because Jin lied and said that he was gonna "teach" Woo, so basically speaking; Jin thinks that Woo still thinks that Jin is teaching him and because of that, he wants to end things. OR I'M COMPLETELY WRONG AND LOOKING TO FAR INTO IT AND JIN IS PROBABLY TRYING TO CORUPPT AND MANIPULTE WOO OR TRYING TO SEE HE WHO WOULD WOO FAVOR MORE 😅😅😅