the head's got some ancestry with the panthers from king gainer and probably canti's dumb tv-head from flcl, but honed down to be less 'monitor' and more 'this is something's head'
i guess you could also say it draws from sonic's mech design as well
meanwhile the gun is made to be as sheer and polygonal as possible (in order to lend to the game's art style) and is also designed in part to facilitate this really goofy wielding style from the, like, very first episode of xabungle, where the user puts the gun on their shoulder and grabs the ass-end of the gun (or even more ridiculous, their other arm's shoulder) with their free hand and fights the recoil with their other arm
this same goofy way of wielding guns shows up in gurren lagann, probably as a homage considering like a dozen guys all do the exact same thing
