A few Monster Monpiece impressions, goods:
~Medium Import Friendly. There's a decent chunk of storyline here and there, and it's difficult to get a grasp on the advanced card mechanics, but it's very playable.
The transformations are very adult. However, the 'rubbing' mechanic seems entirely optional and the only difference it makes is that tapping fills the meter faster, rubbing gets more of a reaction out of the character (blushing/moaning). Each card has 3 or so spots on them you'll need to find each filling about a third of the meter (sometimes 2 for easier cards), you can choose to simply hyper-tap them instead to bypass most of it.
Gameplay consists of taking turns summoning a monster card. Each turn you gain 3 Mana, every monster has a Mana cost to summon. They come in 4 Jobs: Warriors, Archers (Can attack an extra block away), Clerics (Healing Spells), Dark Mages (Buff Spells). You seem to place Mages behind other units to buff them. After summoning you go into an attack phase where you either attack what's directly in front of you, or move forward and attack if then applicable. Summoned units stand still for their turn unless they have a movement skill (blue arrow icon, lets them move on summoned turn), and attack directly in front if applicable.
(Tip: This means you'll typically want to spawn your monster 2 units away from the enemy's, so that they'll move closer, and then you'll move in for the first strike. 1 unit away will get you hit first).
Should one of your monsters reach the end of their field, you'll hit their (life points?) directly for 1 damage. Fodder NPC have 1 life each so reaching it is a win, bosses tend to have more, bear in mind I'm not far in yet.
There are of course more advanced mechanics I haven't doven much into yet. All monsters have a 'type' (such as Dragon, Bird, Hybrid). You can summon a monster of the same type onto another to buff it in place of summoning it separately. There are also various skills they can have, and various buffs that can be applied when certain units are summoned in conjunction, but that's a bit of a language barrier atm.
You can't win by pushing one row, as they can endlessly clog it with summons. You need to pressure two at the same time for one hit to be unblockable.
For each battle won you earn money and 'P-Points'. Money can be spent on card packs of 1 or 3 cards, and P-Points (among items) are spent evolving the cards.
Bads:
Card packs have very repetitive draws, although there is a large variety.
(Potential bad) Evolving cards (strengthening) them strips them of clothing, whether this is a good or bad feature is up to you. The evolution is something you wouldn't want to be caught doing!
No Screenshots.
Seemingly no way to view the card artworks in full-size outside of transformations. Could be I just haven't found it, but if there isn't, ouch!
There's DLC for in-game boosts (free cards, evolutions, etc).
To summarize I'm having a lot of fun with it at the moment (despite the difficulty curve), although I'm not sure I'd recommend it. It takes some effort to play past the language barrier, nevermind the partial-nudity. But it's definitely worth a try for anybody who's willing to put the effort and likes CCGs with fanservice. And of course, the chance of hell freezing over that this will ever get localized.