How can a bad friend be harmful to have? Use an anecdote

A bad friend can be harmful to have because they can make you start to make you do bad choices and in the long run if they're a bad friend they most likely aren't a real friend they could get u into bad things and bad habits

They can be harmful to have if they can get there hands on you as in beat you up or make you do illegal things as in drugs, fighting, and stuff.