I think it's about Gnome being lonely and being approached by a small girl. They became friends and the girl visited her often. Though the girl notices that even though she is growing, Gnome does not, noting that even if she will be a grandma, Gnome will probably be the same (kinda like that Story with Sphinx and the first Sabasa King). When the girl, now a woman, marries, she wants Gnome to be there, possibly as a groomsman. Then a lot happens and just like the girl predicted, she is dying and Gnome is still the same. Thus she asks for her grave to be in Safaru, since this is the place where she first met Gnome, her best friend, and she does not want her to be lonely.
That's the end of the flashback and everyone is sad after hearing that. Nuruko especially and she gives Gnome a bundle of sweets, similar to what the girl did when she first met Gnome. Sonia says that Gnome does not have to feel lonely anymore, since she made new friends. Gnome and Nuruko became friends after that.