Prettydog200 is one of the more notable fans of MarissaTheWriter stories. She has shown both traits of a reel fan and a falmer troll. She has written a story set in Portal High School, The Chronicles of DA SUs (under the alias WheatleysGurl), and she also has MSTed TEEN FORTRESS 2.
She was a reader of Skepkitty's blog, The Half-World, and once references the The Half-World in her MST of TEEN FORTRESS 2. She also frequently left comments on The Half-World, in which she predicted the appearance of falmer trollz in-universe before they actually appeared. Her MST also once features her self-insert, BERZERK MAN, a name taken from the name of her blog, "HIT THE BERSERK BUTTON!" He doesn't get to do much except stripping in the middle of action.
In Invader Zim: Born Again Christian, Prettydog200 is the leader/"liter" of the Teen Ragers, a group of bullies opposing Gloria Deschanel for no apparent reason, and is shown to have an inclination towards bestiality. She, along with the other Teen Ragers, is set on fire by Dib and becomes a Flame Ranger. Her further fate is unknown.
Not much is known about WheatleysGurl, besides the obvious fact that she has a crush on Wheatley.
"Prettay Dog" is briefly mentioned in Enchiridion Marrissa, as a transgender MSTer. However, no other details about this version of Prettydog200, presumed to exist in the main Marrissaverse, are known.
- Fanfic MST #1: TEEN FORTRESS 2, a Team Fortress 2 fanfic
- The Chronicles of DA SUs (previously known as The Chronicles of Invader Zim)