They are in love,
They have had the undercurrent of sexual desire for ages now,
Khushi also wants him. But being traditional and being a girl she is more restrained. Her mixed signals are nothing but this confusion of love versus traditional values.
ASR wants her from the day he saw her in the red saree and he still does. Being a guy he has had his moments of weakness in the past which has grown more frequent recently. His recent aggression is nothing but a need to own her body and soul and make her his wife in every way, kind of put a stamp on her, because this is also a way of stopping her from leaving the contract marriage.
So if you look at it from the perspective that they are two lovers, who have known each other for months, desired each other, shared some intimacy on and off (flashback to the kiss and miss scenes and the many hugs), what happened when ASR wanted to consummate was a natural progression of this love and desire.
He is the same man who has lived with this girl in close proximity and never once forced her. He even put a Lakshman Rekha between them.
Khushi is the same girl who has almost always given in with some shy protests.
So this moment was long expected.
It was just a moment between two lovers and two people in love.
So that part of it felt just right. Arnav may have shown aggression, but to his credit he has always been restrained and he also stopped, which is a tough call for any guy. He did respect her wishes.
Now as for why it felt wrong to many.
What was supposed to be a mutual moment became his choice. It felt like domination.
What was should have had a prelude with roses and sweet talks began with a scolding and a command.
What was supposed to be a sweet moment between a husband and wife, did not ring true because they are not really husband and wife.
What was supposed to be natural became unnatural because the contract would soon end and as we know the affected party is always the girl.
What rankled was that this girl has still not got a proper, decent wedding and he has only started respecting her in front of the family and giving her love himself. So it felt too soon.
It is the ASR'ish part of it which had so many posts that he did not respect Khushi's wishes. So it felt wrong to many. Combine thi with the history of how he has always treated her in the past, things do feel very wrong.
But looking at it from ASR's point of view, he loves the girl.
He has already decided he is never going to let her go.
He is clueless about rituals and their importance. This is the same guy who wanted live in with La.
He is clueless about her feelings for things like rituals like most guys are (sorry guys)
He is in the throes of passion which he has controlled for one and half years.
He has concluded that he wants her and went about it in his own style.
...So call it wrong or call it right'but the intention was simply to take their marriage to the next level 'and give it a semblance of permanence'and give their love a culmination'and finally exercise his rights as her husband'which he eventually did not.
'The whole judgment angle is because of the past and what ASR has done to Khushi in the past'
But looked at in isolation, the guy was simply giving in to feelings and love'yes it was selfish to not consider what she wanted'but if you see he only knew how serious she was about the pheras when she stopped her'.and then he did stop.
This is perhaps my longest post where I am perhaps defending ASR. But this is my unbiased view. Whenever ASR errs in love, he gets the benefit of doubt. It is only when he errs in hate, that it is really tough to take...you see one can't help love, but one can help hate,