Constance Lenz is a supporting antagonist in Black Christmas (2006).
Biography[]
Constance married Frank Lenz and deeply despised each other for unknown reasons. After Billy is born, his father has deep affection for his newborn son. His mother, on the other hand is disgusted with the baby. She even goes so far as to drop broken glass in his crib.
Sometime before Billy became five, Constance had been cheating on Frank with another man.
When Billy became five, she tells Billy he isn't going to get anything for Christmas. She lied to him saying the Russians murdered Santa by shooting his sleigh down, much to her husband correcting her. Soon after, Constance's lover shows up, and the two of them murder her husband and bury his corpse underneath the house. She then locks Billy in the attic, giving him no human interaction at all.
Seven years later, Mrs. Lenz is trying to get pregnant but is having trouble conceiving with her new husband as he is discovered to be impotent. She hears Billy in the attic one night and decides to go up and ground him but everything goes wrong and billy rapes her
. 9 months later, Agnes is born. Agnes is her mother's pride and joy, and is given the life Billy never had.
Eight years later, on Christmas, Agnes is opening gifts from her (grand)mother. Mrs. Lenz, growing tired of Agnes as well, goes into the kitchen to answer the phone. Billy is on the other line threatening her and Agnes. As she runs back in the living room, Agnes is gone. Her and her husband run up to the attic to try and find Agnes. But then hear screams down stairs. They walk in to find Billy tearing out Agnes's eye and eating it. Billy's stepfather tries to attack him, but Billy impales him on a Christmas ornament, killing him in one hit.
Death[]

Billy strangling Constance
As she tries to flee, Billy strangles her with Christmas tree lights. He drags her body into the kitchen and violently beats her to death with a rolling pin.

Constance's body after being beaten to death
After killing her, Billy then cuts large chunks out of her back with cookie cutters, which he cooks and eats, where a few police officers discover him and incarcerate him.