Sidepiece

[Sarah]

The jamb, or cheek, of an opening in a wall, as of door orwindow.

[Tanya Shivari]

A woman whose one level above a jump off but always below the wife. A [sidepiece] must know her part. While he may meet your family. You will never meet his. A sidepiece is a women he will never commit to. A sidepiece will never be [wife material] only an [easy fuck].