Sirris (Sirris of the Sunless Realms) Dark Souls III Guide
Last update: 11 May 2016
Firelink Shrine
Sirris can be encountered for the first time in Firelink Shrine after you talked with Anri and Horace at the fireplace in the Road of Sacrifices. Then she will appear here after you deliver the Dreamchaser's Ashes found in Farron Keep to the Handmaid (at the Old Wolf of Farron bonfire). Speak with her again and you will be able to summon her before the battle with the Deacons of the Deep, Abyss Watchers, Dragonslayer Armor and Lothric. During this conversation you will also receive Darkmoon Loyalty gesture which will be later needed for receiving the Blades of the Darkmoon.
Irithyll of the Boreal Valley
After defeating the beast at the bridge and resting at the bonfire you can return to the bridge behind the barrier, towards the place with the note. If you followed Sirris quest, you will find a call for help here (screen).
After using Sirris sign you will be moved to her world, to the same bridge. You must help her in the battle against Creighton the Wanderer. The fight isn't hard, together you have much better chances. Start with attacking the opponent and luring him from Sirris. Hit enemy's back and hide behind a shield or perform a dodge when Creighton will swing his axe at you. After winning the battle you can return to the bridge. Go to the Firelink Shrine where you will find Sirris again. For the help you will receive the Blessed Mail Breaker and the Silvercat Ring.
Note: After defeating Creighton for the second time, this time in your world (after leaving Church of Yorshka you must walk slightly to the right and up, until you are attacked among the tombstones. It works when you used ember), you can return to the bridge. There you will find Mirrah Chain Set (Creighton's Steel Mask, Mirrah Chain Mall, Mirrah Chain Gloves, Mirrah Chain Leggings).
Undead Settlement (after the battle with Aldrich, Devourer of Gods)
Go back to the Undead Settlement after the battle with Aldrich. Before entering the arena on which you fought the Curse-Rotted Greatwood you will find a covenant left by Sirris (screen). Go to her world and help her in battle with Holy Knight Hodrick. Try pushing him towards the rocks where he won't have much place to move and will be vulnerable to attack from both sides. This should allow you to kill him quickly.
Note: Go back to the Pit of Hollows after the battle. At the bonfire you will find Hodrick's armor set.
Firelink Shrine
Go back to Firelink Shrine and speak with Sirris again. Accept her pledge. Then leave the shrine and go towards the cemetery. On the left side of the road, next to the opponent that watches the view (screen) you will find a grave and next to it Sunset Shield.
After the battle with the brothers in the Grand Archives you will find the White Hair Talisman in the same place.
Note: During this whole quest joining the Rosaria's Fingers will make Sirris your enemy. Only after collecting the shield and then the talisman the quest finally ends.