Can anyone tell me how to properly start with interrogations? Whos hould be the first one? Can I actually blackmail everyone? Where do I find the blackmail material?
You should start the investigations after collecting all the clues at St Thais Cathedral.
In terms of order, I believe you can start with any girl. I personally did Eve, Miriam, Theresa and lastly Delilah.
For blackmail, I believe the objective
is to blackmail the nuns, since you would want them to be on your side. So yea you can blackmail all four of them.
There is no blackmail material per se. I think you'll be able to successfully blackmail them if you've answered the interrogation questions correctly. Dont quote me on that though.
To be successful in interrogations, you have to first set the mood correctly, either using goodcop or badcop tactics. Then ask them the 3 questions and answer them correctly, either (i) agreeing, (ii) pressuring or (iii) accusing them of lying using the correct piece of evidence. Do that and you should be able to blackmail them.