In the same family as Superman Dat Ho (See "Superman Dat Ho"), The San Diego Chicken occurs when a male ejaculates a large amount of sperm (or "liquid love" or "baby batter" as my brother from another mother calls it) on the back of his girl. Then at some point, later, awake or asleep, the male takes a feather pillow and pummels his girl. The pillow burst open and your girl is feathered.
The other night I came all over my girls back. After she fell asleep I hit her with a feather pillow and it burst open. In the morning she was covered in feathers. She look like the San Diego Chicken walking out of the bedroom.