Magical Girl Raising Project Vol. 1 (manga)

Magical girls like Snow White and La Pucelle have dreamed of the day they'd become one of the lucky few chosen to protect N City. But those dreams quickly turn into a nightmare when the Magical Girl Raising Project management office issues a decree-there are simply too many magical girls! Oops! Time to cull the number by...half ? Half sounds good. Don't worry- retirement just means...you die. Good luck, girls!