Jason Ritter must really like TV shows with the word "girls" in the title. On Parenthood, his character Mark Cyr dated Sarah Braverman, played by Lauren Graham, the woman behind Gilmore Girls' Lorelai Gilmore. In his upcoming Fox sitcom Us & Them, he dates the younger Gilmore girl, Alexis Bledel. Next, Ritter will guest star on Girls ' fourth season, playing a character named Scott in its sixth episode. At this rate, the 2 Broke Girls might want to prepare themselves for a visit.
In the case of his Gilmore Girls-connected series, we know a lot about Ritter's characters. On Parenthood, Mark was Amber's teacher and later became engaged to Sarah, before she broke up with him for Hank. The last we saw, Mark had happily moved on and was engaged to someone else. Us & Them, based on the British series Gavin & Stacey, hasn't started yet, but according to Fox's description, Ritter will play, "pharmaceutical copywriter GAVIN...a neurotic Woody Allen-ish personality with indie-rock looks, who has never been in love." The show will follow Gavin and Bledel's Stacey as they take their online relationship into the real world.
But what about Girls? All we know is that Ritter will appear in the sixth episode as Scott. It's not much to work with, but let's guess how he could be connected to the series' main characters.
We know Hannah will be going to the Iowa Writers' Workshop next season, so Scott could be someone she meets there. Maybe a friend, classmate, teacher, potential love interest who will come between her and Adam, or some combination of those.
Marnie's love life was kind of all over the place in Season 3, so it wouldn't be surprising if by next season's sixth episode, she's still looking for the right actually available guy. Scott could easily be someone she goes on a date with, though likely a bad one since he's currently only set to appear in one episode. Another possibility is that he's someone Marnie works with, either at the new gallery or through her attempt at a music career.
Like Marnie, Scott could be someone Jessa dates or something completely different. Since the last time we saw her she was helping Beadie commit suicide until she changed her mind, Jessa might meet Scott after getting in trouble for that, through community service or another rehab facility. As the most unpredictable character, however, if Scott joins the series through Jessa, there's really no way to guess how.
The third season also left Shoshanna in an uncertain place, after she found out she couldn't graduate because of a failed class and begged Ray to take her back. Maybe Shosh is taking a summer class to make up for the one she failed and Scott is a TA or fellow student. He could also be a love interest since Ray wasn't very receptive to her pleas, or even a coworker if she managed to sort out the school issues and get a job.
Hopefully HBO will soon reveal more about Scott because right now, the possibilities are nearly endless.