Flcl, pronounced Furi Kuri or Fooly Cooly is an anime that aired in the Us in 2001 on Toonami, made by studio Gainax. The story follow a 12 year old boy named Naota living in a boring town that nothing special happens in. One day he meets a mysterious woman/alien/schizo named Haruhara Huruko. When I say "he meets" I mean he got hit by her vespa. She realizes she can make use of him and procedes to force herself into his life. Mecha fights, interestrial space cops, and other weird things follow.

The same Gainax that made Gunbuster, Otaku no Video, Nadia, and Evangelion. Gainax was kinda in a interesting situation after making Eva, they had alot a money lying around without many future projects happening. So Gainax let the team do what they wanted, which led to the creation of Flcl. Tsurumaki was the director of it, you can see his style of sekai-kei and the themes of growing up put into the story. He attempted to make the story a short but compact experience.

There was a manga actually published before the anime even came out. The mangaka of it was Ueda, also known as the person that did the eds and some concept art for Monogatari. He's also done other manga like Q-Ko-Chan. The manga itself is a even more compact, shorter version of the OVA. It differs in some aspects, but is a relatively faithful adaptation otherwise.

The music was done by The Pillows, probably being their most known work. They've done the soundtrack for all of FLCL and it's sequels. The music played such a big part into me falling in-love with FLCL. They blended the music and show so well. In the highly emotional scenes have a build up that's usually let out in a following action scene. Or just the quite guitar playing in the rare resting periods of the show, with characters reflecting on themselves. While I like all of songs for me the best tracks have to be "Last Dinosaur", "Beautiful Morning With You", "Ride on Shooting Star", and "Carnival". I think you should also listen to The Pillows in general. I recommend "Happy Bivouac" or "Please Mr.Lostman" to start with their discography.

While we dont technically know, its been suggested multiple times by different people that theyre weren't even planning ANY sequels to FLCL. As I metioned earlier it was more of a fun art project for new and old creators to flex their creativity after they had excess money to burn. Nothing more nothing less. Gainax had a lot of excess money from Eva, they blew through it extremley fast. Matter of fact, they almost went bankrupt. They were so broke that they started to borrow money from Anno. Thanks to Anno we know a decent amount of events that took place, through interviews of course. Anyway, they kept borrowing from him and so he made a deal with them. He gets FLCL and Gunbuster, and they keep getting money from him. Without interest too, which is insane. He was pretty much doing them a favor with that kind of deal.
Before the deal was finalized Gainax drew out of it saying they want event more money.

Later on Tsurumaki, was approached by Cartoon Network in 2008 to discuss possible sequels. He declined multiple times, but eventually agreed after they kept pestering him. Then they went to Production I.G who agreed to it, the company that helped with some things during the production of FLCL. A little bit after that, Flcl was sold to Production I.G after the rights became available..

The sequels themselves are regarded as mediocre or bad by the community, including myself. They lack the story and understanding of the original while also trying and failing to recapture the uniqueness of the original. I really don't recommend watching any of the sequels.