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.
This is used to set specific animation for male and female avatars.
Animation male : Animation can be specific to Male Avatars only if it is added here.
Animation female : Animation can be specific to Female Avatars only if it is added here.
NPC : NPC can be placed on the furniture by dragging and dropping the Statue(NPC) in the scene here. To read more on how to create an NPC in scene refer to Statue.
To know more about seat improved watch the tutorial shown here