The actor that played Godzilla loved the costume and wore it so much. He would barely take it off, and it would even get to a point were he would take the suit without TOHO's permission. But one day, when they did try to take the suit off, it wouldn't budge. After taking a closer look, his muscle, flesh and bones had moved and stretched to fit the suit. His skin fused with the suit. He "became the suit". Inside the TOHO building he was referred to as "the man in the suit", and any information that left the building about "the man in the suit" would result in the person spreading the info not just being arrested, but most likely killed.