Open up your game folder, navigate to renpy/common/00console.rpy
Open it with Notepad or another basic text editor.
Find the line with config.console = false and change it to true.
Open the game and hit shift-O to open the console (that's the letter, not a 0).
The code to set your max arousal/lives/magic to max are player.stats.max_(hp/sp/ep) += (value)
The code to change your stats are player.stats.(Power/Tech/Int/Willpower/Allure/Luck) += (value).
Alternatively you can do player.stats.Exp += 100000000 to give yourself a hundred million xp so that you shoot to lvl 400 instantly.
Keep in mind this is the renpy console, so it's entirely possible to fuck up your save (just like you could do with any editor). There's also a page on the wiki for other commands. One thing to note is that it's case sensitive, and there are still things that can either instakill you (such as the Tengus in Will-Power Temple).
Here's the link to the wiki page: https://monstergirldreams.miraheze.org/wiki/Console