Nah, no way, imp is pretty good. It's the only class with infinite cards/abilities. You can't attack directly, sure, but the ability they have by default (the one represented with a horseshoe) reappears if it's used on an enemy. and since that ability moves like a knight piece in chess, you are outside of most enemy's range when you start it and can avoid a lot of damage. Imp's other cards allowing you to paralyze the enemy just means using the knight skill is even easier.
I'd place it on the same level as the sheep.
Cat girl has some very basic abilities, though that "move back and attack the enemy without wasting a turn" is pretty good. her jump also has decent range, though it's just worse than what others have. It's a mediocre class only really good while learning the game, though I like the appearance of the cat mc, the moving one more tile in every direction is pretty comfy and I've gotta give cats some point for being able to shred clothes though. :V
Harpy is just worse dragon, there's no two way to say it. You have less abilities and the ones you have are worse. You can't even start a zombie apocalypse convert monsters into allied harpies/dragons like dragons can. The best part is being able to fly over the level and just ignore every monster girls since you're 6-7 tiles above them, but other classes can also do it.
Harpy is just there to transition to dragon.
Ram is pretty good, especially since a lot of enemy ai will make them rush you so it's easy to embrace them, or kiss them if you're a bit lacking on hp. Hypnosis to make them relly rush at you, thus making embracing even easier. Very easily abusable.
The ability of the foxes to grow stronger the more fox card they have is ridiculously good and ramps up very quickly since they get two cards from chests instead of one. One ghost isn't enough? No problem! You've got two more fox cards in your hand so there's actually 3 ghosts on your side! Completely Broken class.
Werewolf makes you a juggernaut. You rush through the level, beat everyone up with your very strong attacks, attacks that don't waste a turn and absurd range, and everyone who doesn't die in one hit gets stunned instead. Also, remember the cat girl paw object? The one that doubles your attack on everyone except catgirls who will instead always counter your first attack? Being a wolf turns it into "wolf claws" which is the same but affects everyone equally. Very fun. Hadn't noticed there was a second version though.
And then there's the dragon. You can fly above the level, paralyze and hypnotize the enemies, and you've got ridiculous range on your attacks. On its own that's very good but your eggs you throw have the ability to turn any enemies caught in them (and killed I think but they deal 3-4 damage so almost everything dies to it) get turned into allied harpies and dragons (who will then be able to convert more monsters). Can't aim with the eggs? No problem! One of the attacks (the one where you slam on the ground) automatically turn an enemy into an egg which you can then throw! That's a free convert.
10/10, would start a zombie apocalypse again.