Okay, first off, here's where to find the FAQ & Support link:
KamiPro - Rerolling guide-faqbutton.png

The delete save button is at the very bottom of the FAQ page:
KamiPro - Rerolling guide-deletebutton.png

It'll ask to confirm if you really want to erase the data:
KamiPro - Rerolling guide-confirmdelete.png

...And that's it.