Responses
How do you verify you’re over 19? It seems to want korean phone number or internet ID
You can upload a photo of a valid ID! I used my passport, blurring out all important info except for my name and birthdate. Click on the "My page" section on Bookcube and you'll see a 1:1 inquiry button there. Clicking on that will lead you to a page where you can send an authentication request to their customer service team. Hope this helps!
For readers who have disposable income, do consider supporting the author! It's fairly easy to sign up for Bookc ube using Google Translate. I'm waiting for my adult certitication to come through so I can buy more chapters (づ￣ ³￣)づ