Anti-espers are espers with the ability to neutralize other psychic powers same as ECM. There are also anti-espers with specific ability that can cancel out other anti-espers much like ECCM neutralizes ECM, allowing other espers to use their powers even in the presence of another anti-esper. In the pilot chapter,Kōichi Minamoto is also an esper with level 7 negation of anti-esper powers