Fifty Shades of Grey has become a phenomenon that seems to have marked this century with modern-day BDSM awareness.

Is it all the submission-and-dominance, or is it the love story that made the book so popular? Or is it both? This is one of the things that girl friends discuss over booze and coffee when the book comes up in conversations.

Here are the Top 5 Things that Friends Discuss Over Caffeine and Booze

5. Who to cast for the role?

Fans know the lead characters Anastasia Steele and Christian Grey by heart, that they have specific ideas on who to cast for the roles. There have been reports that the film producers would go for upcoming instead of established actors, but relatively big names like Matt Bomer and Emma Watson have led online polls, anyway.

4. The erotic parts that make up the book, and what could be tried with their partners

While other girls would rather keep their bed tales to themselves, those who have questions on what they've read in 'Fifty Shades' have questions that needed answers. This is when the previously secretive other girls begin to talk.

"I've been tracking media for the past 17 years for NCSF and there has never been any kind of reaction like this before," says Susan Wright, a spokesperson for the advocacy group National Coalition for Sexual Freedom.

Speaking to Hollywood.com, Wright says James opened a topic for discussion for the readers.

3. Just how bad is the book, really?

Not everyone who has read 'Fifty Shades' are fans of the fiction. There are those who have read better erotic fiction. There are others who were unable to read past the first few chapters (the early parts before erotica kicks in) because of James' weak narrative and repetitive expressions.

"I read all of them and while I found the love story touching, I found all the books poorly written and and often incorrect as far as the BDSM is concerned... You have to really understand BDSM to write about it and it's obvious that E.L. James didn't do her research," says the 76-year-old Desiree Holt, a romance author.

2. Why is the book so unputdownable for the others?

What makes the book unputdownable for others, and detestable for the rest? Why do other readers read it again? (Book critics say it is not the finest work of fiction, after all.) Is it the love story of the lead characters, or is it what they do in bed (or other places)? Or is it both?

1. The things Christian Grey do for Anastasia Steele

When girls talk about actors to cast in the film, they talk about their own perception of Christian Grey's vibe and looks. Moving forward into the conversation, they talk about the things the pop fiction hero does for his submissive. In some instances, some girls begin to wonder if they could meet their own Christian Grey. This is when the realists in the group smacks the others to say: It's all fiction, and it's not even well-written at that.