Notes:
Use F to open the shop menu/inventory. There is no actual farm; you use the money from slaying monsters to buy more food. There is no way to re-order your inventory (that I can tell), but it's fine to leave it empty until you want to feed a monster, then just buy that food and it will go to the front of the queue.
Use R or T to *recruit* new monsters that like you enough. It does not rotate followers, and it doesn't work if your party is full (4 monsters max, no way to release them).
Use Q or E to *actually* rotate your party.
Click monsters to cause a pop-up showing their stats and their feelings about food (plus/minus hearts). Health and mana are top right, relationship hearts are top left. Black relationship hearts are negative. Pink hearts are positive ones.
Click the turn number to see how much money you get per kill and how many hearts you need to tame monsters on the current floor. Both change every floor.
No idea how to get your monsters to attack, but they certainly need to be next to or inside of the enemy and you can tell if its working or not by the presence or absence of animations for attack or magic there. Magic in my experience does not do enough damage to be worthwhile, and also your followers will attack you with it constantly which can be annoying (but luckily not very threatening).
There's no end, as far as I have found. And all monsters can be converted easily given your plentiful resources. Also the displacer beast can solo most enemies no problems.