Nekoba, in case you're wondering, is short for "Neko Bazooka", and in this game you play as a badly-drawn cat with a bazooka, shooting various weird things in at least three kinds of stages (I haven't completed the game yet, maybe more appear later?). There's platform stages, driving stages, and helicopter stages.
The platform stages are the most numerous, and they take place in closed-off areas where you have to kill all the bosses that appear within the time limit (and obviously, without getting killed yourself). The driving stages see you stand on the back of a pickup truck shooting a cop cars and busses until a boss appears for you to kill, and the helicopter stages are short, but somewhat traditional horizontally-scrolling shooting stages.
This is a game that really feels like what I think of regarding the term "indie": it seems to have been made by one person, who clearly had ideas about the game they wanted to make, and let nothing stand in their way. The art is wildly inconsistent, with high detailed artwork of anime girls talking to crudely-drawn blobs in the cutscenes, and all the enemies in the stages are a seemingly random assortment of more crudely-drawn animals, parodies of existing characters (including the very brave inclusion of what appears to just be a distorted low resolution piece of official mickey mouse art), and just strange monster things. All this, and a lot of the music is actually vocal songs!
Is it actually fun to play, though? Yes! It's definitely not a tightly-crafted experience, but each stage is only a couple of minutes long, and they're some incredibly frantic minutes with enemies and bullets all over the place. The difficulty is just right, too, as it never feels like a tedious cakewalk, or a punishing slog. Likewise, the enemies all take just enough punishment to make them satisfying kills without feeling like damage sponges. Come to think of it, maybe this is a tightly-crafted experience, merely disguised as a demented piece of outsider art?
Anyway, Nekoba Rock n Roll is interesting, fun, unique and also very very cheap. So you should probably go and buy it!