How does this affect our heroes?

At first, they don’t notice.

“So... what’s so important you need my book.” Timmy asked Samantha as they leaned on the couch, watching Melody eat Chad’s ass.

“The stuff I’m made of doesn’t obey your laws of physics.” Samantha told him. “The RSEs allow us to exist here for a short while. Outright possession of a human host is rare.”

She ran her had over his shaft again.

“Then why does this thing look like a book? Why can I change the world?”

“The book isn’t exactly the RSE. It’s only the controls for it. It’s a bit like the TARDIS.”

“Wait... how do you know about Doctor Who?”

“I know quite a lot about human culture. I’m assigned as a custodian to this sector of the multiverse. It’s part of my job.”

“So, how does the book work?”

“Well, it’s like any other computer, you enter a command, the system executes it. In this case you’re writing them down. Long story short, it uses an ability similar to mind control nd it’s beyond space and time nature, to affect probability in the past. We use that to have a suitable host exactly where we need them when we need them.”

“So...”

“Tell you what, write something down.”

Timmy took the book and began writing “old rule, men have long, well made hair.

Timmy watched as Chad’s hair grew from a buzz cut to massive waves of locs.

“Wow.” Timmy said, playing with his new longer hair.

“So you see why I need to leave.”

“One last question. You said you needed to go when you got the book. You’ve got the book, why haven’t you left?”