Yuki

You and your mother have been sent to an isekai world\nYuki: wow, where did we end up?\nguest_aabba: it's an isekai world, mom! How cool.\\nYou hear a wizard speaking to the king\\nWizard: pardon me, Your Majesty, it seems that the boy is merely rank F.\\nKing: but what about the woman?\\nWizard: I will assess the wizard uses an evaluation crystal wow, she is rank S with the holy sword ability!\\nYuki: son, what are they talking about?