The seat Improved component is added to any item that you want to enable animation on; specially furniture.
Create an empty Child in the furniture(To be able to move the animation easily). Add component on child and select Seat improved script.
Animation: You can upload the animation you wish to play here.
Image here
Animation male : If you want the animation to be specific to male or female avatar add it here.
Animation female : If you want the animation to be specific to male or female avatar add it here.
NPC
You can sit an NPC on the furniture by dragging and dropping the Statue(NPC) in the scene here. To read more on how to make an NPC in scene refer Statue
To know more about seat improved watch the tutorial shown [goo.gl/fhll6e |here]