Seems like this chapter just about wrapped up the Mole Hunt arc. I decided to analyze a bit more than I usually do with my chapter reviews since there was a lot to talk about on the Twiyor front!
When Fiona questioned Twilight about not killing Yuri, he gave his official "for the mission" reason, but slipped up by calling Yor "Yor-san" instead of "Yor Briar." This made it obvious to Fiona (who already knows about him softening) that he's trying desperately hard to cover up those feelings. Even though this would have been a good opportunity for her to imply that she's a better fit for the wife role, she doesn't even try because she knows Twilight would defend "Yor-san" in every subtle way he could.
When he gets home and finds out that Yor doesn't actually have gripes with him, he's relieved of that last load of stress and is finally able to relax, causing him to collapse (similar to the very first chapter when he collapsed after Anya passed the Eden entrance exam). After he realizes how utterly exhausted he is, he can't help but ask Yor to help out with his housework.
Her reply is what really makes everything sink in for him - despite all his attempts to be a flawless spy, she doesn't want him to be that way. She's happy when she can be useful to him and thinks it's bad if he pushes himself to be perfect all the time.
And yet, that's exactly what he has to be in order to survive as a spy. The fact that he had to ask someone for help with simple housework, plus someone telling him that he doesn't have to be perfect, made him recall the feeling he had when he looked into Wheeler's eyes...that he lives in a world where you have to be perfect in order to survive, and having any kind of weakness just won't due.
While Twilight continues to be clueless about Fiona's feelings for him among other things, what he does realize at the end of this arc is his own feelings - that he does have a weakness. He's beginning to understand more than ever that a spy can't afford to be anything but perfect. And yet, his refusal to kill Yuri, which is a result of him caring about Yor (even though he gave Fiona his usual "for the mission" reason, she saw right through it) is conflicting him even more.
I also have to point out how considerate Yor was of Loid's exhaustion - she completely pushed Yuri away, even after noticing he was injured. She didn't even invite him to stay and have tea with them!
What Twilight was about to say to Yor (in his mind) before Yuri interrupted is debatable, but going by his previous line of thought, it was probably something bittersweet like "which is why...once Operation Strix is over, I'll have to leave the Forgers" or possibly something more immediate, where he now realizes how compromised he truly is and so might reconsider the stipulations of Operation Strix even before it's over. Though I think it's more of the former since his thoughts in the shower in the next scene make it seem like he's not ready to do anything drastic yet, but the idea is still gnawing at him.
Fiona had noticed his leaking emotions way back when she was first introduced, but this is the first time Twilight himself is realizing it and not denying it. Whether anything major will change in his actions from now on is yet to be seen. Will there be another aftermath chapter or two with Twilight still being jostled by this realization? Or will things go back to normal now and he'll brush those feelings aside for another day? It seems like Yuri has been totally thrown off the scent, so his identity should be safe for the time being. Will Anya get to read his mind the next morning and finally find out everything that happened? The next new chapter won't be out for another 4 weeks, so brace yourself for a grueling wait!