All things considered, this game is very fun! I'm a big fan of dice-based games, and the level of risk-reward gameplay they provoke (especially dice-builders like this one), and making your dice actual physics-based objects was a nice touch, too. However, I feel like that mechanic might've needed a bit more work, since the faces seemed... less than random at times. I have had at least two instances where the die just... bounced into the air and spun around, without the top face changing at all. It's fun and all, but the dice being in such a small area restricted your ability to really "fling" them, and thus reduced their randomness (or, at least it felt like that sometimes).
I also liked how combats often ran very close to the wire, and you had to use your health as a resource to take out as may enemies as you could before going on the defensive, although the range of difficulty that produced close enough combats to leave some team members knocked out, but not totally destroying your party and making you lose, was a bit thin. But all in all, that's a minor complaint.
I wish the Corruption mechanic wasn't as much of an "insta-win" button; as is, it feels like you have to corrupt a party member to win (which, yes, I get that was the idea), but, once you do, it feels way too drastically easier. Like, I lasted as long as I could without corrupting a party member (to the black minotaur fight, in case you're wondering) and only then corrupted two of them. But I can imagine, if I corrupted earlier on, or corrupted more of my party, I'd have a lot more time to build their strength, and it would've been really easy. Having that as an option available, and expected of you, takes away from the accomplishment of beating the game otherwise. Unless corrupting earlier on makes their movesets weaker and healthpools lower.
Furthermore, this is mostly a personal preference, but I don't like smut games where you have to lose to see the smut. I get that it fits thematically, but it feels like it's rewarding the player for failing, and punishing them for succeeding. That sort of thing only works for me if the game at its core is difficult enough that you will be failing a lot, and it thus acts as a way to cheer the player up. Something like a roguelike/lite or bullet hell, for instance. As applied to this game, this would only really work if: 1. the game was hard enough where you're expected to lose multiple times, each time only corrupting one or two party members, OR, 2. the game was hard enough that you'd need to corrupt all 4 party members to win the game. It feels less satisfying to play another round just to see the other party members' transformations, than to experience them naturally in gameplay, especially when the combats aren't even randomized, reducing the replay value somewhat. But, again, take this with a grain of salt, as I might be bothered more by this than other people.
Anyways, moving on from my rant/very coherent game critique. I liked the art and the art style a lot. Each of the 4 main characters has a lot of personality, in their base and transformed states, and I can't complain about art quality at all, really. The only complaint I might have is giving some of them different "attack" sprites for different moves (ie. the Druid's base attack vs heal vs stun, or the Warrior's base attack vs shieldbash/block). And I also would've loved to see some sort of "epilogue" feature, showing how the characters lived out their lives after being corrupted or not corrupted by the dungeon. Honestly, I was 100% expecting something like that at the end, and was surprised to see there wasn't one, or at least some variance in the end screen art showing the characters' silhouettes changed.
So yeah, that's my thoughts. Overall, I liked the game a lot, as the amount of critique I've written on it should probably make you assume. So, don't confuse my amount of critique as me not liking the game, quite the opposite. I'd be glad to see wherever you take this game, if you decide to update it further, or to see whatever sort of game you come up with next!