So essentially, Marginal Prince is based on a cell phone dating game. Since they couldn't really include the "main character" of the girl, they pretty much just removed her. Unfortunately, they didn't really have anywhere to go with the storyline without her, so they clearly made up a story on the fly. Plus, with the main character now being Yuta, it comes across very BL-like, despite not being actually BL.
Most of the show is a series of largely unrelated events that introduce a large number of underdeveloped characters, and the attempt toward the end to tie up some of the vague plot threads is too little too late. Out of the characters, I found Henri, Red, and Sylvain to be at least interesting, but even then we don't get a lot of development, they're just the ones whose personalities stand out at all.
On top of that, the creators wanted to stick with what was apparently a theme in the dating game--the singing. As I was once told by a friend: "They burst into song at least once an episode whether it's appropriate or not. And it's never appropriate." The music is actually enjoyable, pretty standard VA theme song fare, but it generally makes no sense with the story and often ends up being hilariously out of place and/or overdramatic.
As I said before, this show is enjoyable because it's bad in ways that make it funny. If you're looking for a laugh at an overdramatic weird musical anime, it's probably worth sitting through at least some of, although it's short enough that watching it all is doable. If you're looking for a GOOD former dating sim anime, I'd recommend Meine Liebe.
