For every word of my praise that comes out....
...along comes quite a few phrases "and the horse you rode in on!".
The game mainly uses a combo of Mouse and Keyboard, similar to a shooter I saw called Big cat or something like that, and shows the one weakness of a lovely invention created by one Douglas Englebart, the computer mouse. While quite accurate, sometimes pinpoint, it is never quite as accurate when forced to be so while moving in a set path or moving quickly. For instance, when you move your mouse at something, your hand's momentum will usually make you overshoot by a small margin. Or, that if you take your hand off your mouse, it will "jump" a bit.
These things make games that require careful dextrous movements of a mouse through a hazardous path...a sharp pain in the rear. Doing this with a time limit while also having to control another character is almost maddening. I guarantee almost no one will be able to get to the final level with any points gained from level 1.
This is made even harder by the fact that in order for the cooperative parts of the game, where you carry your more tangible buddy around, he can easily fall off, even with the slightest, brisk stroke of the mouse. Much of the game will come from you trying to find the balance between moving slow enough to keep your passenger safe and fast enough to avoid death. Moving one's mouse off the game screen is always fatal, as the mouse will always zip back to the spot where it reentered, making the ghost ram the nearest forcefield.
Worse yet, there are parts where you are forced to maintain your ghost's position in a tiny or moving space whilst manipulating the guy with the keyboard, that can make you forget about it or cramp up your hand making sure you are perfectly still while doing the jumping.
The guy's jump is also a terrible, iffy jump (Jumping straight off the ghost girl...never works!) and the jumps required need a bit more playtesting, as a jump I can only make 50% of the time and I'm not allowed to use the ghost girl as help feels a bit broken.
The fact that both characters can die independently of each other (prompting the restart of the stage is infuriating, as you can get so far...only for the ghost girl to accidentally bump into something and you have to do it all over again. Why does the ghost girl need to get to the exit portal as well anyway? Shouldn't it be just the guy? And how can the ghost girl die again? Couldn't she just reform elsewhere, without us having to restart everything?
As the previous paragraph is full of gripes, you'll be right in guessing this game is hard. Really hard, particularly past lvl 4. But the premise itself is novel, the story is silly, and the boss fights (while sometimes aggravating) are very good exercise for multitasking.
A good idea would be to try and play with a friend, or, "buddy" of yours, and try and team through it.
Hope for a sequel, where the ghost shoots lasers, and the field merely stuns the ghost (Consider how lethal that'd be for the Sadako Boss? You throw him above Her, accidentally get stunned, and now there's no one to catch him before he falls into the hole!)