Where to Find Irina
You should make your way to the Weeping Peninsula, which is located at the very tip of Limgrave. After crossing the Bridge of Sacrifice, activate the site of grace that is to the right of the path, and then continue to the south along the path until you see her sitting near a low wall on your left.
She will tell you that her comrades were attacked and killed, and she will ask you to take a letter to her father at Castle Morne to let him know that she is still alive. She will explain that her comrades were with her when they were attacked. There is a connection between this and the Edgar Questline.
How to Find Irina’s Father
After you have arrived at Castle Morne, you should go through the courtyard, walk past the Pumpkin Head, and then climb the ladder. Fight your way past the misbegotten, both on the ground and in the air, that guard the wooden bridge that leads to the upper level of the courtyard. After you have crossed the bridge, you should head in the direction of the soldiers and Misbegotten who are engaged in combat to the northeast rather than descending to the Site of Grace. They are fighting each other.
It is possible for you to run past these foes because they are focused on killing each other; however, we recommend that you make a stop along the way to eliminate them. By doing so, you prevent any of them from following you to Edgar’s location, where they could accidentally kill him and bring an early end to both Irina’s and Edgar’s respective questlines. Continue in a northeasterly direction from here, then climb the stairs, and proceed around the corner to locate Irina’s father, Edgar.
Upon delivering the letter to Edgar, he will express gratitude that Irina is alive and well; however, this is not sufficient to advance the quest. If you want to continue the quest, you will need to find another way to save Irina. This is the game’s way of letting you know that you need to defeat the boss in this area before you can move on to the next one. He will mention that he is duty-sworn to continue to protect this castle.
Proceed to the very bottom of the castle, onto the sandy shores that are speckled with jellyfish, and across to the golden fog that marks the location of the entrance to the boss arena. Gain access and vanquish the Leonine Misbegotten within.
Finishing the Quest
Returning to Edgar at this point and letting him know that the task at hand has been completed will enable you to access new lines of dialogue and will cause him to proceed to the next location. To access the concluding part of Irina’s questline, you will need to make your way back to the location where you first discovered her.
When you go back to Irina, you will find Edgar kneeling over her dead body, and he will make a vengeance oath against whoever was responsible for what happened to his daughter. The conclusion of Irina’s quest can now be found here. On the other hand, this might not be the last time you see Edgar…