Penchant/WMG

Sun is the Slender Man.

PATH is the Robo-Rasper.

Macey is the Robo-Rasper

• She's been calling Andrew to warn him while possessed by the Slender Man.

The blog is run by only one person

• Meta guess here, but the writing style of Macey, Andrew, and Tyler seems very similar. I presume one person may be behind all of the posts.

A.A.F is in on the whole thing

• He's one of the people who writes the blog commenting on another account.

Alternatively, Sun is some sort of code word for a safe haven for Slender Man

Tyler is a Time Lord

• It's Tyler TIME.

PATH is the Robo-Rasper, or connected to him