Earwigs are insects that can cause damage, sometimes serious damage, to plants, flowers, fruits and vegetables. They leave jagged, small holes in leaves as they feed on them. They are most active during the night, and a person would be hard-pressed to find them during the day because they usually hide. They are not known to establish homes indoors and can be found outdoors, especially where vegetation is present. Earwigs will not cause damage if found indoors, unless of course, there are houseplants available for them to feed on, in which case they can destroy the plants.
Though earwigs are unsightly, there is no indication that they have been able to dig their way into a person's brain. They do move very fast and can emit a liquid that's brownish-yellow in color and smells foul. They do posses forceps on the end of their abdomen and have been known to pinch slightly if a person does not use care when handling one. They are long, flat insects that can be either a black or a brownish-red color.
There are no known effects to humans, except for the occasional pinch if picked up carelessly. Despite what their name might indicate, they are not known for attaching themselves to either humans or to pets, though entering the ear canal would probably be possible if an animal sleeps outdoors. However, it's not likely that the earwig would stay there very long sincere there isn't any vegetation on which to feed. Plants and other vegetation are the only things that are threatened by earwigs.
If earwigs find vegetation, such as in a garden or a flowerbed, the effects can be devastating. While one or two earwigs will not cause much damage, but the same cannot be said if a large concentration of earwigs are found in an area of vegetation. The effects of their feeding habits can cripple a garden and devastate a flowerbed or houseplant.