True, I had forgotten about it, but the potion maker event made it seem more important since she didn't accept the MC's invitation until that last event, no wonder they don't want her to have NTR events.
To recruit the vampire you just have to accept the mission to investigate the vampires, investigate the forest and then you go to the castle. It's not very complicated but she's quite funny she's a perverted pure blood vampire i think she was a virgin but she rapes the protagonist while he sleeps and gets pregnant by him. Her events are somewhat funny