Koharu (小春, こはる, "Little Spring") was a young girl who worked for a man since she lost her family during the war.
History
During the story
She is an orphan who meets Miroku after he is called to her village to perform an exorcism. He gives her some food and leaves, promising to come back for her. Much to the disgust of Kagome and Sango and shock of Inuyasha and Shippō, he even asked her to bear his children at the age of 11, to which she would oblige and bear his babies.
Three years later, Koharu is now 14 and she comes across the path of Miroku again. Before hand though, she was being chased by the Aburachouji's young lord and his men after he tried to force himself on her. She stated that he had his eye on her recently, something that most likely made her feel uncomfortable. Her fears came true that night, when he tries to make her his. She used some fire wood to beat him until he lost consciousness, also resulting in several visible injuries.
After Inuyasha and Sango chased them off, she asks to travel with Miroku and the others but they know that it cannot be. After talking to the village leader, Miroku arranges for him to take care of Koharu. This leaves Koharu deeply saddened. Inuyasha, feeling that her tears are being wasted on "that creep", decides to let the team stay for the night and set out in the morning, only on the condition that she doesn't cry again in the morning when they leave.
As the night rolls by, Koharu is stopped by Kanna who steals her soul with her mirror. Soon after, in her hypnotic state, she attacks Miroku who knocks her out. Not long after, Kagome fires her sacred arrow into Kanna's mirror, and all of the souls that she stole come spilling out, Koharu's included, and she awakens, back to normal. After which, the group leaves, and she is left heartbroken, but does understand his mission, and prays that Miroku succeeds in destroying their enemy, Naraku.