A second lawsuit filed in a California court this week accuses Zillow of being an "frat house" which promotes sexual and ageist harassment. This time, a single mother is suing after being fired by Zillow because she checked into a hospital to treat injuries sustained in a car accident.

Zillow has built up a $4.5 billion valuation by amassing an immense real estate database. But a lawsuit filed in a California court accuses the company of cultivating an "adult frat house" culture in which female employees are constantly solicited for sex by co-workers, ranked on their breast size, and fired if they refuse to play along.