Nyuu's Past ( にゅうの過去 / にゅうのかこ / nyuu no kako ) is the thirty-second chapter of the Elfen Lied manga series.
Leaving the shelter after the rain passes, Kouta and Yuka are despondent over not having found any trace of Nyu. From a short distance behind them, Lucy spots them and thinks back to her childhood in an orphanage.
In her flashback, the younger Lucy is tormented by bullies, led by a boy named Tomoo. They liken her to animals and trip her, content with mocking her until a girl calls for a teacher to stop them. Lucy is reluctant to accept the girl's help and apparent wish for friendship. Withdrawn and bitter because of her abandonment as an infant, her only friend is a stray puppy living near the orphanage grounds, to whom she gives part of her daily meals, but keeps a secret in order to prevent it from being harmed by the bullies. She laments her inability to better protect the puppy, and begins to feel the first stirrings of her hidden power.
Realizing she can't take care of her pet all by herself for much longer, Lucy confides in her new friend, who agrees to give it part of her food, and also swears to keep it a secret. Before long, Tomoo is taunting her again, but this time holding the puppy, with the other girl rushing in and apologizing for letting the secret slip. The boys beat the puppy to death with a rock while another holds Lucy back, the boys laughing the whole time. Lucy sees her supposed friend smiling behind her hands. When the puppy is dead, the bullies complain of it dying too quickly and laugh, only for Lucy to scream in rage. She unleashes her vectors upon the other four children and slashes them all to pieces, literally painting the room with their blood. While this happens, she proclaims they are the "worthless animals".
Burying the puppy in the nearby forest, Lucy regrets she couldn't protect her pup and resigns herself to the fact that she will forever be apart from others because of her horns. A boy appears, asking about her horns, and while she contemplates killing him as well, she is flustered when he joyously proclaims her horns to be 'cool.' This boy was indeed Kouta when he was younger.
- A controversy exists among fans as to whether or not Lucy's supposed friend just failed to keep the puppy a secret or deliberately befriended her to betray her trust.
- This chapter begins an extended flashback set entirely during the childhoods of Lucy, Kouta, and Yuka, and explains much of Lucy's alienation.
- The story never explains why Lucy, previously on the verge of uncontrollably becoming Nyu once again, apparently averts it.
- Yuka on this chapter's cover seems to be wearing clothes suited for relaxation around the house.