The Aunt of Harry Potter.

It's common knowledge that Snape hates Harry Potter because he is the son of the girl he loved, or is he.
The real reason why Snape resents that boy is because his wife was kindapped that cold October night. She was taken while protecting her nephew. Of course Voldemort didnt know she was married to Snape, but he still kept her isolated in a place only he knew.
The other reason he hated Harry. She was protecting him while Pregnant with his child.
Deep down Snape couldn't help but care for his nephew and throw a few threats around to any teacher who dare try and put him in danger but he could still dislike him.
Snape cried himself to sleep most nights wondering about the health of his wife and child.
Her name was Lavender Rose Snape, formally evans and she was the twin sister of the Late Lilly Evans and she was going to come home soon.