It's the MC seeing them. They involve a character that is not a LI (yet, but she's close to being best girl, which makes it a crime) at the very start of the game and our character catches them in the act. Whether they are avoidable or not I can't remember, but they probably are. And if not.. just close your eyes and press CTRL for 2 seconds and they cannot hurt you.
Trust me, it's worth getting over this little hump (if it is one to you), since there's a shitton of content that is worth playing that comes right after!