Firelink Shrine

Talk to him at Firelink throughout the game

Hawkwood

High Wall of Lothric

Free him from his cell, accept to find Loretta.

Greirat of the Undead Settlement

After you have reached the 2nd bonfire, talk to him in Firelink.

Leonhard

Undead Settlement

Obtain Loretta’s Bone, give it tom him in Firelink, send him for scavaging. Maybe you have to reload the area to continue his quest. After you defeat a boss, he will return to Firelink.

Greirat of the Undead Settlement

Talk to him in the elevator, drop off the elevator, talk to him again. Help him defeat the demon. Buy Siegward's armor from Patches, if he is already there.

Siegward of Catarina

Find the ashes near the spear area in Undead Settlement, give them to the Maiden in firelink shrine and buy the key for 1500 souls, open the door next to the shortcut near the Cliff Underside bonfire in Undead Settlement and rescue Irina. Buy Dark tome of Londor from Yuria of Londor.

Irina of Carim and Eygon of Carim

Accept his offer. Go to Firelink and level 5 times thourgh is service. After reloading the area, Yuria of Londor will appear.

Yoel of Londor / Yuria of Londor

After obtaining 1 Pale Tongue, he will give you the Lift Chamber Key to the locked door below the Tower on the Wall bonfire. Head there, unlock the door, defeat the Darkwraith there to obtain the Red Eye Orb. Speak to him at Firelink. Maybe you have to reload the area for the new dialogue.

Leonhard

Road of Sacrifices

Get Holy tome of Carim in the small tomb under the bridge on the way to the 2nd bonfire.

Irina of Carim and Eygon of Carim

Talk to Anri and Horace with all options.

Anri of Astora

Speak with her in Firelink shrine after you spoke to Horace and Anri of Astora.

Sirris of the Sunless Realms

Cathedral of the Deep

Find him within the Cathedral of the Deep disguised as Siegward of Catarina (after opening the main door of the cathedral, maybe reload the area after that). He will trick you into entering the bridge which he will then lower down to the giants. Meet him on the other side. Buy the Tower Key in Firelink and explorere the tower, get trapped again. Buy Siegward's armor from Patches.

Unbreakable Patches

After opening the Cathedral main doors (shortcut near the boss gate), he will be stuck inside a well just outside the cleansing chapel bonfire. Talk to him. Return his armor to him. Not to do so will kill Greirat, because Siegward can't rescue Greirat.

Siegward of Catarina

Get Dark tome of the Deep.

Irina of Carim and Eygon of Carim

Speak to Anri after defeating the boss.

Anri of Astora

He will appear in Rosaria's Bed Chamber once you have joined the Rosaria´s Fingers and offered at least 1 Pale Tongue. This will cancel Sirris quest!!! You can finish his questline after you do Sirris' questline.

Leonhard

Get Dreamchaser's Ashes and give to Shrine Handmaid in Firelink. Reload the area and speak to Sirris. Don't give Rosaria a Pale Tongue or Sirris will become hostile.

Sirris of the Sunless Realms

Catacombs of Carthus

After defeating the boss, he will disappear.

Hawkwood

Find Anri in the Catacombs of Carthus in a hallway before the first rolling skeleton ball. Exhaust all dialogue. Choose dialogue options "no" and "do nothing." Never tell Anri of Horace's whereabouts. Speak to Anri again at the wooden bridge before the boss.

Anri of Astora

Smouldering Lake

Kill Horace, don't tell Anri you killed him.

Anri of Astora

Irithyll of the Boreal Valley

Cross the bridge to Boreal Valley, meet Greirat at Firelink and send him for scavenge again.

Greirat of the Undead Settlement

Talk to him in a kitchen near a lake-like area and share an estus soup with him.

Siegward of Catarina

Talk to Anri, don't kill the pilgrim. Kill the boss, talk to Yuria.

Anri of Astora

Sit at the first bonfire after the entering bridge (Central Irithyll bonfire), go back to the bridge and get summoned by her. Kill Creighton the Wanderer and speak to her at Firelink.

Sirris of the Sunless Realms

Irithyll Dungeon

You can talk to him in a cell.

Siegward of Catarina

Get Dragon Torso Stone

Hawkwood

Profaned Capital

Free him with the key found.

Siegward of Catarina

Anor Londo

Perform the "wedding" ceremony. Get sword from pilgrim and kill spouse. Talk to Yuria. Causes 'Usurpation of Fire' Ending.

Anri of Astora

After Eldrich is slain, go back to Undead Settlement to the optional boss fight place (don't teleport directly into boss area, boss needs to be dead and you need to have the Transposing Kiln). Get summoned by Sirris in the small room before the boss area. Hodrick is a tough fight, and it's entirely possible he will kill Sirris, so approach this fight carefully. After that speak with her at Firelink.

Sirris of the Sunless Realms

Return to Rosaria's Chamber after you reach Anor Londo bonfire and pick up the Orb in front of her. You can use the Black Eye Orb to invade him in the room above Aldrich's bonfire and kill him.

Leonhard

Untended Graves

Get the eyes of the Firekeeper and give it to the Firekeeper.

Firekeeper

Lothric Castle

Clear the castle, then send Greirat for scavenging again. Without clearing, he will be killed. (Needs confirmation/clarification, maybe easier to say after patch 1.04)

Greirat of the Undead Settlement

Get Holy tome tome of Lothric. Give holy or dark tomes to Irina in Firelink, depending on if you want good or bad ending.

Irina of Carim and Eygon of Carim

Her grave can be found after Cemetery of Ash boss fight area.

Sirris of the Sunless Realms

Archdragon Peak

Get Dragon Head Stone and Twinlking Dragon Torso Stone. Defeat Hawkwood at Abyss Watcher bonfire.

Hawkwood

Kiln of the First Flame

Summon the Firekeeper via summoning sign, if you have given her eyes. Causes 'The End of Fire' ending.

Firekeeper