Grisaia: Phantom Trigger The Animation

The characters might not be similar, but I do find the settings somewhat similar. The show tells a story about characters who's related to some sort of an organization that needs them to kill someone the organization orders them to do. Both characters from the 2 show uses guns and arms as a main weapon. 

A healthy dose of spy girls in training but with a legendary spy as their teacher instead of a traditional schoolteacher. 

In both, a secret organization uses cute 16-year-old girls to fight criminals and terrorists 

One assassin guy and harem of of cute assassin girls. Both are quite edgy and give similar vibes.