Any seating arrangement that is only used when a car would otherwise be considered full; four+ people in the back, three+ in the front, or any number in the trunk. Example: I was designated driver, so there were three ultra-bitch seats in my car that night.
ULTRA-BITCH
Meaning of ULTRA-BITCH in English
Slang English vocab. Английский сленговый словарь. 2012