It's been a few years since I've seen one of the craziest anime to greet my eyes and ears, "Kill La Kill" (キルラキル) with its battle scenes...well, pretty much every scene...on acid. I did write about the first ending theme, "Gomen ne, Ii Ko Ja Irarenai" (ごめんね、いいコじゃいられない) which is still my favourite of the four theme songs used during the original run from 2013.
However, the first opening theme, although it never became an earworm to me, is not too bad either, in retrospect. Eir Aoi's（藍井エイル）"Sirius" helps all of us viewers blast into the action along with the opening credits. A fluffier song wouldn't do the show justice and every time I hear "Sirius", I always see Ryuko and Satsuki trying to bash each other into pulp.
"Sirius" is Aoi's 5th single from November 2013. According to Aoi herself on J-Wiki, the song was meant to be an upbeat work filled with the brightness of the teenage years. Well, if it's anything like the adolescence experienced by any of the main characters from "Kill La Kill", I would probably replace that word "brightness" with concepts such as "craziness", "psychosis" and "insanity".
Written by meg rock and composed by Ryosuke Shigenaga（重永亮介）, "Sirius" peaked at No. 21 on Oricon. It is also included on Aoi's 2nd album "Aube" from January 2014. That album got all the way to No. 6 on the charts.
Unfortunately, due to ill health, Aoi brought a stop to her career in late 2016 and for the meantime, it's unknown when or whether she will pick up the mike again.
Now here is Ryuko to show how NOT to drive a bus.