Abhi has not "showed" any emotion for Pragya so far. Because he is not supposed to. But that does not mean that he doesn't have them.
He would be a no.1 loser (in his eyes) if he fell for Pragya, the Pragya who planned her sister's wedding breaking his sister's and even that way caused his bestie to drift away from him.
After that she has done a bunch of stuff against him starting from her regular naataks with Daadi and trying put him in jail, break his guitar and even stay with her boyfriend in her husband's room.
So, if Abhi still shows emotions for a woman like that, it is shameful in his eyes.
That's exactly why he has not made blatant moves on her while they lived together.
Also, he is loyal to Tannu. Whether he loves Tannu or not is a different question, but currently his loyalties are with Tannu. He has even tried to make it clear to Pragya in every chance.
But all this does not mean that he has no emotions for Pragya. He has always had some pull for her, even before the wedding, before he learnt she wrecked his sister's love life.
But his emotions are still there in some deep place within his subconscious. That's why if a restaurant guy "chedo" Pragya, he can't take it. He wants to kill Suresh for sleeping with her. Because at that subconscious level, he wants her. And when he is not thinking through his MU brain, he does react to her positively and possessively. He does not like it, even hates it if others call her stuff.
Is he attracted to her? Oh yes. The thing is it's not her body exactly he is attracted to. It's her, the whole person. Body wise, he might have seen better, but that is not the issue here. But he loves being around her, fighting with her... in general her company..etc...
This is why he can't throw her out of the house at the first instance. He gives her chances although kicking her out would ease his life technically. He can move on with his life, Tannu etc. But he does not do that. He hopes she proves herself. Today Aaliyah instigated him to throw her out of the house again when he was drinking.. But he comes to Pragya and complains (not even once he talks of throwing her out), shares that his reputation is at stake (whether it is really the case is arguable, but he believes so). Just shows his rockstar status is very dear to him.
So was today's scene. He was drunk and his subconscious was speaking. First he worried abotu his reputation etc.. at some point it kicked in in his brain that she has slept with another guy.. but she was supposed to be his, na? He wants her.. he wants to do what the other guy did.. he wants to replace the other guy...
Point is he wants her. He does not even know that at a conscious level.
Hope that makes sense..