Talesh is a female slave that Shallan as Veil impersonates in effort to sway Amaram in his recognition of her while she infiltratates his manor as a Ghostblood.
Talesh herself had difficulty choosing between suitors. Amaram had promised her father that he'd see her cared for. He couldn't do so unless she settled down, as he expressed to Shallan.
Shallan, as Talesh, indicated to Amaram that Hav had stopped a messenger on the perimeter of the manor who had been coming for Amaram. Further, still in disguise as Talesh, Shallan tells Amaram that Hav had sent her back to tell him so.