SOLVED. Adult Thriller or Lit Fiction, 2016-2024: Student at Oxbridge uni, makes friends and joins a mysterious game society. Spoilers. [s]

[rakesh]

Read this a few months back, but cant recall the title. Was on my kindle, but may have been deleted.
Plot is like this.
American student goes to Oxbridge university. Makes friends with another chap, and they join a mysterious game society. They make a pact to keep the game going till then end. They add other members to the group. Protagonist is in love with one of the girls in the group but she falls for his friend. The game is based on luck type rules and dare based acts. One of the participants kills themselves jumping off a high uni building.
It ends with the american student, going to new york, and living as a recluse obsessing over the game. One of the girls from the group gets in touch, and he meets up with her. Cant remember the ending, but that was kinda it.

[Ashley]

Black Chalk maybe?

[Kat]

I think Black Chalk is the book your question reminded me of, too.

Do you remember if [spoiler]

towards the end of the book there's a part where the narrator looks back and realizes that there are parts of the story that he didn't write, or that he doesn't remember writing?

[rakesh]

That's the one. Thanks all!