After killing one of the three vampires, not only the two vampires left are quiet. The monsters watching are also shaking in fear. That mean at least the vampire is much stronger than most of the monsters here. At least that's what the monsters here recognize.
"You are so stupid thinking of attacking me for my blood. Can't you see clearly that I have the Vampire Queen by my side? If she follows me without being bonded by a contract, why would you think of attacking me, huh? Are you looking for death instead?"
I guess I intimidated the vampires too much. What if they refuse to say anything because of fear? Then I think killing them would be much better.
"Roy. Don't you have some questions to them?" Arin reminded me to interrogate the vampires.
"Oh, right. Let's just move to the important part. We're in a hurry, you see. Can you tell me about this monster prison?" I asked the vampires about the existence of this cave.