Mahou Shoujo Ikusei Keikaku

From Yen Press: Suger and Spice not playing nice! 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.