How does Morrison use the color red within her novel, "Beloved"?

In Chapter Eleven, when Paul sent beloved back into the house, he kept his back to her bacause he wanted the sin to stay behind him. He finally said Beloved because she kept repeating the request. She walked closer, he wasn’t aware of her movement; he also didn’t realize that the rusted can in his chest could be a red heart. He continued to repeat the words, “red heart” louder and louder until Denver woke up.

Later, the ghost haunting caused a great deal of havoc on those who lived in the house, Sethe and Baby Suggs knew it was the dead child. They heard her, felt her presence and experienced her rage from within the walls. Sethe had told Paul D that it wasn’t evil that the ghost released but sadness. Paul D felt the sadness as he passed through the redness (the emotions of the ghost) to enter the house.