It's a black hole of cliches, so confident that it can hide behind their immense mass it forgets it needs to be anything more. It almost feels like it was assembled using an anime idioms and tropes mad lib.
The best anime can remain in genera yet be original, because they use the tropes against the audience or invest in some clever alternative use for them. Puella Magi Madoka Magica is the best recent example of this, blending horror and magical girl genera without being obviously ironic, there are many others though. The worst ones use genera as a substitute for creativity, for thinking outside the box or bringing an ounce of effort into the game. Aria is so disastrously cliched it feels like it's making fun of you for watching it. The bouts of "Become My Slave Kinji!!" and screaming wails of "Pervert!!!" along with humdrum scenes where one character walks in on the other during various stages of undress resulting in screeching, punching, and gunfire. Aria literally has gone through them all as if by checklist, every line you'd expect, every situation, all of them. They even have the jealous catfights which were getting old when Tenchi Misaki was still a boy.
It's got the full blown "ain't she endearing" scenes too, where Aria is reduced to socially awkward blushing frenzies with outright exasperated denials of having anything but contempt for Kinji in such a way that makes Toradora appear brilliant in comparison. Then the obligatory damsel in distress scenes, where Aria's tough image, which apparently she's supposed to have, is inevitably blown away as she's saved by Kinji. Who has a literal genetic predisposition to be an over-the-top heroic douche bag. They've got that down to an art form.
As for the plot, or rather the lack of one. Convoluted. is the best adjective. There are anime which can get away with that, but only to a point.
If there is a saving grace of the series, it's the action sequences - had they bothered to work on the rest of it as they did those all too brief occasions - it might have warranted me watching half the bloody thing.
