Genre is a funny thing. More often than not it seems like bands get lumped in with whoever they tour with more than who they sound like, or are allowed to define their own genre when it seems unclear. I would say that this is especially the case with emo, as unwanted a label as it often is, but I'm not sure that's really true. Try to define the edges of indie rock, for example. Very few bands are genre defining, and perhaps only they fit neatly in the box they created.
And then sometimes there are bands which are clearly of a particular genre that just somehow slip through the cracks. In the case of New York's The Forms, I think it might have something to do with the semi-mainstream attention they garnered, including a glowing review for their first album in Pitchfork. They were crowned the next big indie rock band by a bunch of indie rock outlets, and that fact largely papered over their musical inclinations. I have never seen Icarus on a list of emo albums, nor talked about when post-SDRE works like The End of the Rings Wars are discussed. Somehow, this album has the stamp of indie rock all over it, this despite the fact that multiple review outlets drew direct comparisons to Sunny Day Real Estate (The Morning Call had the grace to at least call it "emo-rock," whatever that is).
If this seems a little strange given the comparisons to SDRE, it's absolutely absurd when you've actually listened to the damn thing. Released in 2003, Icarus is mathy, yes, and sometimes art rock-ish, and occasionally aggressive, and maybe even a bit avant-garde, but at all times it is a combination of Diary and LP2, a soaring, operatic work of midwest emo.
The band's follow-up work may also account for their lack of presence in the emo consciousness. Their second album, a self-titled work, sees the band embrace their label and go pretty much full indie rock on it and subsequent releases. Regardless, Icarus stands as a seminal work of midwest emo and if you're reading this blog, you need to hear it.
A note on song titles: I am following the naming conventions of the digipak edition I have, which simply lists the first six songs as 'Stel 1-2', etcetera. While later digital releases have added 'intro' and 'outro' tags to song segments, I'm going with what the band intended in 2003.