The tomato is red"... A sentence passes her by, but it reveals something from a world where the occupation wanted to extinguish all the colors of life, so what did Nida Katamesh see behind the doors of "Demon's Tomb"?

The tomato is red"... A sentence passes her by, but it reveals something from a world where the occupation wanted to extinguish all the colors of life, so what did Nida Katamesh see behind the doors of "Demon's Tomb"?