Kanamemo - Vol. 1 Ch. 11

[MangaDex]

 

[alfirizkyr]

Not sure if this is the intention, but I think the punchline in the first pages about Yuki being the 'cat' is that the bottom/receiving one in a lesbian relationship was apparently called neko in Japan. They're basically accidentally 1) implying that they know Yume and Yuki had sex, and 2) calling Yuki the bottom to her face.

I might just be reading too much into this, though.