Claymore, Garo: Honoo no Kokuin Recommendations
Swordsmans fight against demons, who mask behind casual people. Violence, dark fantasy atmosphere and other similar nuances. And overall feeling Garo remind me Claymore.
Both take place in a Medieval time period, involving a group of people set out to kill monsters that disguise themselves as humans so they can feed on humans. Like in claymore, Garo involves fast paced action where they have insane speed and superhuman strength.
Unlike Claymore however, Garo has a conclusive ending (unless you include manga)
Main character part of an order that has been created to fight dangerous demons that eat and take the form of humans they've devoured.