
Long story short
They both trained and got to know each other in original TG. First, Touka didn't like Kaneki because he was a half-ghoul that could endanger everyone at anteiku and Kaneki thought Touka was scary. So, they got to know each other, risk their lives for each other. After Kaneki got tortured, he wanted to become stronger to protect her, Touka starts to worry about Kaneki.
Then he forgets who he is (not gonna spoil how that happens), Touka cares about him so much that she rather him stay happy as Haise and not tell who she is. He cries when he sees her after two years as Haise, she is the only real person he remembers and he thought that how could he have known someone so beautiful
So, their love is like a slow burn...not super obvious or super quick...it develops from the original, manga all the way to :re manga.

No girls can't like boys. Only boys can like boys.
Okay, so in my time when I used to read Tokyo Ghoul, there was a kind of issue.
I never quite understood why Kaneki and Touka fell in love per say.
I love them together, don't get it wrong. It's probably the only 'straight' ship I have ever loved this much.
But I didn't quite understand their love for each other.
Maybe I need to read it again or something but then I dropped it about 2 years ago
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