The film hints at the ending in the first few moments of the film itself

Every few months, I keep revisiting it because of its fascinating storytelling. Even though the ending is known, it has that quality that when one watches it again, there is a thrill to catch all the hints. Aisa lagta hai saare jawaab mere samne hai, lekin mujhe nazar nahi aa rahe hai.
_

Latesha:
It's scary and borderline psycho.
(8 September 2016)

Latesha:
For you to be attached for me still after this long does not merit meeting you.
(8 September 2016)

Latesha:
You still have feelings for me, Whatever happened was half year ago and it wasn't even that serious.
(8 September 2016)

Latesha:
I've said all there was to be said.
(8 September 2016)

Tessa:
I'm bleeding a week after unprotected sex and it was my first time. I had sex the day I was off my period. What could be causing this?
(8 September 2016)

Tessa:
My friends made sure I didn t go to bed until I was calmed down which took a long time.
(8 September 2016)

Tessa:
I was sweating and having trouble breathing and staying up.
(8 September 2016)

Tessa:
They were close to calling 911, but by that point the worst was over.
(8 September 2016)

Tessa:
I m also a pretty mellow person and I don t act out like that, ever.
(8 September 2016)

Tessa:
Keep in mind, this is what my friends told me the next morning that were taking care of me.
(8 September 2016)