One of the optional side quests within Elden Ring that relates to helping Rya get her necklace back
Rya can be found and located just north of Laskyar Ruins, where she is standing inside a tower.
WHERE TO FIND RYA
You can find Rya just north of Laskyar Ruins, where she will be standing inside a small tower. Speak to her.
Speaking with Rya you will learn that some thug managed to steal her necklace, she wants it back. Apparently this thug is Tarnished. Agree to help her and we will then learn that this thug should be resting at an abandoned home.
FINDING THE THUG
After your conversation with Rya continue on north a little bit in order to find an abandoned home (Boilprawn Shack) and more specifically the thug.
At Boilprawn Shack there will be a site of grace that you can interact with. When you are ready speak with the thug.
The thug (Blackguard) is willing to part ways with the necklace but you will have to pay 1000 runes first. If you keep speaking to the Blackguard his merchant inventory will increase, he will now be willing to sell a Boiled Prawn.
Purchase both Rya’s necklace and the Boiled Prawn
(Note: You can also get the Spread Out emote gesture by speaking to the Blackguard)
REPORT TO RYA
With the necklace in hand report back to Rya. She will then introduce herself, apparently she serves Lady Tanith of Volcano Manor. We will then receive the Volcano Manor Invitation
Head to Volcano Manor and you will be able to find Rya in the Drawing Room.
(Note: You can get the Drawing Room Key by speaking with the lady in the chair over in Volcano Manor, she sits next to both the fire and a knight)