Pubic hair
A line of hair from the navel toward the penis is sometimes called a happy trail or treasure trail. If there is a narrow line of hair from the navel to the pubic patch above the penis, the pattern is called sagittal. On some males, there is an upward-pointing triangle shape. In that case, the hair pattern is called acuminate. On males and females, hair pubic hair usually extends down past the pubic region and ending at the anus (the hole between the buttocks). In females, hair will cover the outer lips of the vagina; in males, hair will grow around the base of the penis and lightly cover the scrotum (the outer sack containing the testicles). Depending on each person's genetics, the amount and extent of hair can be different from one person to another.