Bunny Must Die (InstanceTopic, 18)
From Compile Worlds
Bunny Must Die, subtitled Chelsea and the 7 Devils, is a doujin platformer where you play as a Genki Girl who can't decide if she's a bunny or a cat is a playboy bunny and got cursed to having cat ears at the same time as bunny ears (Wouldn't taking that outfit off from time to time help?). Well, Bunny's "naive" motivation is to go find whoever the heck procured this annoying curse (literally: any mention of her cat ears and she'll probably kill you) and get rid of it. Unfortunately, things don't quite turn out to be that simple.
Apparently, the majority of the fanbase prefers Chelsea, but this troper Kumizonian can't figure out why, since Bunny has over 9000 kickass acrobatic moves, can manipulate time and can change her breast size at will, whereas Chelsea is slow, boring and her most powerful attack is a... ladder. Well, it is fun hearing NakaTeleeli say "Ladder~", but that's a point to him, not Chelsea.
The game's Japanese title is the rather long-winded チェルシーさんは7の魔神をブッ殺さねばならない。 (Chelsea-san wa 7 no majin wo bu korosa nebanaranai., punctuation included), often abbreviated as チェルのブ (cheru no bu). It roughly translates to "Chelsea must kill the 7 devils", though Google insists otherwise.