[kishen]

There are only three scenarios that can happen here

Scenario 1: Meera and Desai get into the act but here Krish's reaction is very unusual. Because he was waiting for it to happen and it was not the first time Meera did it without him knowing it beforehand. So, he was in tears and all that does not make any sense to me or rather I would say Krish as an author could not create that emotion perfectly.

Scenario 2: It was Desai but with some other partner, but that does not make any sense as to why would he take such a risk just to create confusion in Krish's mind. I think that's too much risk for nothing. I would say this is less likely even though earlier I said it is also a possibility.

Scenario 3: This one is very outrageous but, hear me out. What if Meera did it with someone else?? Who knows Meera's fling with Ashish was not a fling and they are in a relationship and for some reason, they could not control their excitement and decided to do it in Meera's home thinking that Krish is invalid also rooms are soundproof.
I know this is simply outrageous but it will open up multiple possibilities.

Technically, the first one makes more sense but they have been there multiple times in the past and came back together, so, I don't know how it will create a situation that will end the story.

Meera has cheated on Krish on multiple occasions and later she confessed it or Krish had knowledge about it in some way or other. Like Meera had sex with Desai for the very first time without Krish's consent and also gave Desai a blowjob in his car which Krish heard. She also had sex with Ashish but later confessed so it is not that she is doing it for the first time. And I am not suggesting Krish should not feel the way he is feeling right now but it was not conveyed properly. If she had sex so what?? She will confess it later and like every other time in the past Krish will enjoy it why he has to tear up and be sad?