Hmm The cat saying "Main Shrine" (or "Main Temple/Main Castle" in the previous chp) kinda confused me, but I have a sudden realization now about it probably trying to refer to MC... If it's translated from 主殿 I'm inclined to think that the meaning (in this context) should be Master-dono as the title the cat used for addressing MC, in which 主 as in master and 殿 as in an honorific suffix like -sama for 様. 主殿 could literally mean main shrine/etc at least in Chinese/Mandarin, I'm not sure if it's the case for Japanese, but it's unlikely to be about any main shrine/etc in this context I guess...
*Don't hit me, I can't read Japanese, I can only read Chinese (Some kanji of Japanese too because of their origin) so I'm just sharing some thoughts and hopefully it'd help 😌