I think the cat is San ancestor. He was Eunjae's dog before, so I think is likely

Eunjae’s dog was in the same timeline with san tho …

I'm talking about san's ancestor not him, the one that appear in the past and raised geumsung

I see … interesting take tho!! I’m still not sure about what geumsun said about the kitty, but I’ve heard that the next few chapter will be quite interesting for you considering the cats identity!!