ERIE, Pa. (AP) -- An approximately 300-pound woman has pleaded guilty to third-degree murder for killing her nearly 120-pound boyfriend by beating him with a table leg and sitting on him, rendering him unable to breathe.

Authorities say 44-year-old former home health aide Windi C. Thomas entered the plea in Erie County court on Monday, agreeing to a recommended sentence of 18 to 36 years.

Defense attorney Mark Del Duca says Thomas passed out on top of 44-year-old Keeno Butler as a result of drinking. He says it wasn't intentional.

Del Duca says the "actual cause of death is she collapsed on him and he basically died of suffocation."

Prosecutors say she stabbed him in the hand and head and beat him severely in the head with the table leg.