Who do あなた will be affected もっと見る with Katherine around Damon または Stefan? And why?

Damon! Because he was in 愛 with her and now that she left him, he tried to find her, when he couldn't because she was already out of the tomb and because she didn't want to come back to him.
Now that he has fallen in 愛 with Elena all of a sudden Katherine just pops up. Then she says that she has never loved Damon, which is terrible! Also, then they make out? WTH! He can't control himself with her, even though she doesn't 愛 him, he starts making out with her! Katherine will have a lot of affect on Damon for all of this! All he REALLY needs is Elena who will bring out his soft side, his humanity.. Then hopefully at the end of season 2 he will realise that he doesn't want または need Katherine.. He WANTS Elena instead.. Elena isn't a 雌犬 to him, she doesn't like pkaying games. Although she is with Stefan, Elena will 愛 him as well, then the 愛 三角形 begins!! But Damon will HAVE to kill Katherine!! または someone else, but hopefully Damon because of all the terrible things that she did to him!
Stefan will feel surprised and angry that she's back because he knows that Damon can't control himself with her and he might do terrible things! Katherine has come back for STEFAN not Damon, that's probably going to hurt Stefan knowing what Katherine is playing games with Damon.. Even though Damon won't realise it. Stefan might feel a bit もっと見る cautiuos.. And will fall in 愛 with Katherine again... But honestly, Damon is going to have the MOST affect from Katherine!

I think that Stefan will be もっと見る affected.
Damon will be hurt for sure and he may return to his "I don't give a damn about anyone" style, but he's been there before. I think he realized that Katherine doesn't 愛 him since he found out that she wasn't at the tomb. He will be surprised and hurt to hear that from her, no doubt about that, but he will eventually come to terms with it...
Stefan on the other hand,for 145 years was certainly sure that Katherine was dead, so there could be no him and her. So he didn't try to get over her (REALLY get over her),he just accepted the fact that she was gone. Now the fact she's back and she says that she came back for him, will provide him with an alternative that he had never thought... Therefore he will be もっと見る affected cause he will lose the balance he had in his life...