"Harry and Snape's relationship reminds me more of the interactions between a teenage girl and her mom, where both have anger management issues because they literally reflect it from each other,' Ensnapingthesenses wrote.

There are other notable textual examples to support the trans Snape theory, according to Ensnapingthesenses—small things like, during a flashback in The Deathly Hallows, when the child Snape is seen wearing her mother Eileen's blouse. Compellingly, in The Half-Blood Prince, Harry and Hermione examine Snape's handwriting in an old copy of Advanced Potion Making, not knowing who the self-appointed "Half-Blood Prince" who had written in the margins of the book is. (It turns out to be Snape, and the "prince" moniker is a reference to her mother's maiden name.) An excerpt speaks for itself:

Harry wondered vaguely who the Half-Blood Prince had been. Although the amount of homework they had been given prevented him from reading the whole of his copy of Advanced Potion-Making, he had skimmed through it sufficiently to see that there was barely a page on which the Prince had not made additional notes, not all of them concerned with potion-making. Here and there were direc­tions for what looked like spells that the Prince had made up himself.

'Or herself,' said Hermione irritably, overhearing Harry point­ing some of these out to Ron in the common room on Saturday evening. 'It might have been a girl. I think the handwriting looks more like a girl's than a boy's.'

'The Half-Blood Prince, he was called,' Harry said. 'How many girls have been Princes?'