Spy Classroom, Vol. 1 (light novel): Lily of the Garden (Spy Classroom (light novel), 1)

INTELLIGENCE IS THE MOST DANGEROUS WEAPON Following a devastating military conflict, countries fight their wars in the shadows. One unusual spy, Klaus, has never failed on the job despite his quirks, and he is building a team to take on an Impossible Mission—one with over a 90 percent chance of failure. However, his chosen members are all washouts with no practical experience. They’ll have to use every trick in the book (and some that aren’t) to prove they’re up to the task! When every country in the world engages in a shadowy war of espionage, there will always be work for those who are willing to take on the risks. To answer the call, the world's greatest spy creates an organization dedicated to tackling missions considered impossible...though it remains to be seen why the seven members of this group all have no experience!