I don't agree. What would be the point of their dynamic staying the same through the whole story? Of course, what was happening between them back then was really amazing, like pretty much unique, but that dynamic needed to end for them to start a new phase of their relationship.
Well, it's not exactly a relationship right now, when one side is an obsessive psycho, and the other blind to it, by design, I might say. But this is not the end game, guys!
And yes, it was the rape scene that brought up most of the changes, but not all of them. Uno's cautiousness started during the bar scene by Enzo murdering his own men. He is afraid of Enzo, which he wasn't before. But he's just too bold to let that fear dictate his actions, too proud to let Enzo win, even though since ch.14, the game has been rigged against him.
Uno's the only one who's been trying and trying again, while everyone else folded. It's kind of nice how stupidly stubborn he is to win, never giving up. Even while dead afraid for his life, he went back to that restaurant, just to score some information. And he's not exactly stupid. He made a lot of blunders even before meeting Enzo. That's just his personality; sometimes he gets lucky and it works in his favor, sometimes not!
I might sound like a Uno's fan... because I am~
No one is saying that their relationship has to stay the same, but the new dynamic is neither interesting nor pleasant to watch... at least for me. The explanations for Uno's actions also make no sense, because they contradict everything we know about him from Red Candy. Uno was supposed to be the ace among spies - experienced, with many skills and knowledge. Who meets with a person who told him not to use sex as a solution in a room where he just had sex a moment earlier? It's just stupid. Like many other of his other actions in the middle of the plot.

I feel like this isn't what they promised me at the beginning with this title. I liked the game between them, who would come out on top this time and the chemistry was great back then! But since that rape scene... everything has gone downhill.
-Uno seems to have lost all his brain cells and keeps acting like he started working in the spy industry yesterday (he makes very basic mistakes).
-Ezno stopped being cute and started being an annoying creep.
-The chemistry between them is completely dead (where did the burning desire and tension from earlier go???).
I'll read the next season in the hope that it will improve, but I won't be looking forward to it.