Yeah, game's a bit confusing at first due to all the various stats, but is easy enough to understand once you think about it a bit.
Main things to grok:
You've got 4 employees who choose various places to be each day, either randomly or semi-randomly based on some internal logic I don't understand, and it is then your job to shuffle them about in the three time slots as you see fit. Difficulty here comes from the fact that you only get to do this a limited amount of times per day per employee, and it stresses them out (how much they like you determines how much you can shuffle them). The places they can be are the three break rooms (each associated with a work stat, for example the gym with endurance), or one of the guest rooms, such as the slimes.
Now the guests have a number of variables that you have to find out: first, each of them responds to the different work types differently. For example, 'Interact' work on the slimes increases their 'Pressure' gauge (the red one) based on the amount of Intuition the person working on them has (the three work stats mainly respond to one of the three gauges, though there are exceptions to this), whilst doing Maintenance work on the slimes increases their 'Resolve' gauge (the green one) based on the amount of Stamina the person working on them has, BUT it also decreases the 'Pressure' gauge by 2 bars.
Your job with the guests is to try and get all those bars to max as often as you can for rewards (and also because it keeps them from breaching), as well as satisfying their unique daily requirement (which for the slimes is very easy: all you have to do is *not* do Maintenance work on them twice or more in one day) for ease of upkeep and also because it keeps them from getting angry (again, for the slimes, the reward for not doing maintenance work is an automatic one bar increase in their Resolve gauge, which incidentally is also what the Maintenance work increases, so basically, they will auto-maintain themselves every two days as long as you don't do Maintenance work on them at all).
Hopefully this meandering example will prove some help to somebody, don't really have the time to edit it into something more structured. Regardless, I do think this game has some promise, even though it's a bit obtuse at first.