Viability: Definitely felt cohesive and thorough until the end, only problem I ran into was a missing image in one passage.
Presentation: Good use of typography and color, along with some images to help set the scene. I would love to see even more illustrations and color choices if you choose to continue this one, the Kaiju theming is awesome!
Theming: Really fun theme for a dating sim, I would love to see how the gameplay mechanics could become even more complicated using this theming if you choose to continue.
Engagement: Story was engaging and fun to make choices in the world you have built. Just a suggestion, but if you choose to continue with this I think adding some sort of incentive for choosing certain dialogue and adding more monsters would be good. Solid engagement though all the way through.