"Defeat the fifth boss." Yaeger thought that these words would be enough to deter Zeke from asking any further questions. However, Zeke didn't stop. On the contrary, this fueled him to go even further.
He turned his back on the goddess immediately after she said these words. When Yaeger asked what Zeke is planning to do, the human answered with confidence: 'I'll defeat any monster you throw at me." This made the goddess roar in laughter, completely forgetting the fact that, Zeke is nothing like the other humans which she has encountered.