Baby Blue Sedan

To clarify, "all the eunuchs, they were standing in rows singing, 'please stud us out just as fast as you possibly can'"

Traditionally, if a young male could sing well before he hit puberty, he would be castrated so to preserve his voice. A "stud" is an animal, such as a bull, that is kept especially for mating. So to "stud out" is to put out a bull (or horse, etc.) for the intent of breeding. So in this song, Isaac is just adding humor by saying that the eunuchs are standing there singing, demanding that they be studded out. This is impossible, given that they are castrated.

It's incredibly clever.

I suppose the song could relate to a prom, as was mentioned - that would fit, but Isaac doesn't seem the type to write about high school days. But the "white suit" would obviously be the formal attire for the dance and the "baby blue sedan" referring to a more or less shoddy means of transportation to the dance, hence, "and I am doing the best that I can." Then it leads into the end of this dance, "sad song, last dance, and no one knew who the band was" - pretty self-explanatory. Someone he knew, Henry, was probably a terrible dancer, and stood stiff and didn't really move much, like a wooden Indian.

It all fits, but seems unusual that he would write about something like that.