It's because they're both tops.

Indirectly saying Yuuka isn't.

Levander said:

Indirectly saying Yuuka isn't.

Moe, even youkai moe, and topping generally aren't paired together as character traits.

Levander said:

Indirectly saying Yuuka isn't.

If the knowledge I've got from the doujin is trustworthy source, Yuuka is the bottom

Looks like Remilia is discovering that Sakuya.exe cannot operate properly without Meiling.jpeg

Ominous_Owl said:

Looks like Remilia is discovering that Sakuya.exe cannot operate properly without Meiling.jpeg

Now that is an obscure reference