If something goes Against The Grain it moves against the natural flow of feelings or events. For example, a man, who hates the theatre but will go with his friend who loves theatre, might say, “Well, even though it goes against the grain, I’ll go along.” The phrase was originally a woodcutter's saying and has been in use since the 17th century. It is much easier to cut or carve along the grain of wood than cutting across (and so against) the grain. Working with the grain is smooth and easy; against the grain is hard and unnatural.