Sakura and Shirou
The two of them looked at Breeze with utter bemusement, wondering what the hell she was talking about. Sakura, being good at hiding her feelings, was mostly able to avoid giving any indication of her thoughts, but the look on Shirou's face made it clear that he thought she was a moron.
Deciding to be polite, Sakura was about to answer her extremely-stupid question, only to be interrupted by the other girl who, to their astonishment, went on to actually claim that a "sakura" was, in fact, a species, of which the girl presumably thought she was a member. This time, even Sakura couldn't hide her astonishment, a look of surprise and confusion coming over her face. An entire species named after her, made up of people who, presumably, all looked similar to her? Was she in one of Rider's fantasies or something?
Before she could react, though, the girl contined to speak, giving her a funny look before questioning Sakura's decision to marry her beloved Senpai. Sakura gave the girl an annoyed look in response, unhappy at hearing anyone question her Senpai's suitability as a husband and confused as to why she would have an issue with the idea. Was it some weird cultural restriction where this "Mary" girl was from, perhaps?
"Why wouldn't I be?" she asked, obviously a little annoyed and very confused. "He's perfect in every way, why wouldn't I have married him? And what's wrong with marrying a senpai, anyway?"
"And what do you mean about Sakura being a species?" she added, even more confused. "Are there more of you? And do you all look like me?"
Shirou, meanwhile, turned to the other girl, now wedged into the alternate Sakura's thighs, a look of total bemusement on his face.
"Y..yes, there do seem to be a lot of girls who look like Sakura around", he said. "I bought a pet from one a few months ago. And Rider says that she's seen a few more Sakuras around, too", he replied.