Fairy Gone

Because they are both an action-oriented, somewhat political, post-war drama, that share a similar premise and setting. After fulfilling their role as “weapons of war”, the “Fairy soldiers" (Fairy Gone) and “Incarnates” (Abandoned Sacred Beasts) must now adapt to living a peaceful life in society, or be hunted down. Both shows feature a male and female duo that go around and investigate disturbances caused by the former soldiers. These soldiers have a supernatural ability to summon/become monsters; which in turn creates conflict among society.  

If you like dark storys with magic where the main character learns how to use his abilitys and makes friends alongside a tragic backstory. I recommend watching them! 

Both shows contain similar attractions, with spiritual forms specific to each user, who are able to provide either offense or defense. In both cases as well, the protagonist is unaware of their possession with said entities but is quick to get used to them  

Same animation, same studio and similar atmosphere. both anime has back stories which happens in their village. both are supernatural and action. MC has dark past and both aren't well quite normal human.  

Both series take place with similar time periods and settings; there's corrupt empires, shadowy organizations doing unethical things, and a good mix of guns and swords at play. As in Fairy Gone, Magatsu also focuses a lot on setting and world-building rather than intensive character development (a fact you either love or hate). Overall it gives off a similar vibe. If you like one, you may find a lot to like in the other.  

Both anime deals with detective agencies. Both anime has male and female protagonist working together. 

Both shows are military based that take place in old times. The MC's of both shows are in a special military unit and posses special abilities that normal humans don't. In "Fairy Gone" and "Mars red" their foremost task is to create a peaceful society. 

The anime are on a group of gifted power beings trying to hunt down villainous made creatures in the midst of world destruction 

The same set of characters with special abilities that deals with their own kind whom were the bad guys.  

The same plot that involves an organization that deals with the supernatural, and the people who uses them.  

both anime about fairies and mythical creatures that are almost extinct, both about investigators protectingthe fairies 

The powers of the characters in both anime are very similar as in both cases the characters summon monsters that they can control to fight for them. 

The same plot that involves member of an organization that have special abilities and takes the job of handling bad people with special abilities.  

-Both use weapons that change based on the user -Both are action animes with well-written female characters -Both have kind of weird animation styles