In the locations of Morbuk Bogs, go to the Hotel and start a conversation with the innkeeper. Say that you want to treat all people with beer for the whole night (it will cost 6 ducats). Then ask if he needs help (you need to kill the rats far away, you don’t have to go, you can kill them when you go to the location behind the hotel), after completing the task, don’t take money. Then he will tell you to approach the militia Mirosh.
Talk to Mirosh about Ilra (who wanders at night) when you finish talking with Mirosh, go to Ilra and start a conversation about what she saw when she wandered at night.
When you end the conversation as she saw their leader with an unknown person, you get experience for this, but the question does not disappear. Can be repeated endlessly.