For anyone confused about getting all endings;
Good Ending: Either free Mal0 early and ruin your friendship with Si-Won or release her later and refuse to let her go.
Neutral Ending: Keep Mal0 caged.
True Ending: Release Mal0 later and let her go.
Bad Ending: Don't let Mal0 expand her territory or manipulate real world objects. Free Mal0 later, then refuse to help Zellen in act 3.
I just did another playthrough for the true ending, so here's what you have to do (Warning: long post).
After completing night 1, research methods to gain admin control, then hack the laptop when you get to night 2. When the power goes out, tell the girls to wait upstairs and meet them in the VIP room. When you first get the option for research, save your game, then start with paranormal.
When night 3 starts, paranormal should be at 150. Replace the camera first, ask Zero for a hug in the security office. After that, clean up blood, and restock soda. Pet Fexa if you wish (I do did it because she needed it). End the night with by researching coding.
Spend an hour in heaven with Zero to get paranormal at 200 and missing persons at 50. Once night 4 begins, vacuum booths, and restock energy bars. End night 4 with missing persons at 150. Then cuddle and research with Zero to get paranormal to 350. After that, ignore paranormal until coding and missing persons are maxed out.
For night 5, restock vodka, replace camera, and prepare dough. When you get a text from Sawyer Peck, have Zero get his address. This is important because you need to talk to him for Frenni's real name. Do research on coding before ending the night.
After talking to Sawyer Peck, you can either leave him alone, or have Zero haunt him (something funny happens if you choose the latter). Research missing persons before starting night 6. Have coding at 300 at the end of the night.
Go to the magic shop and buy the Memory Obliteration Counter-Ward and Thunderstorm Ritual Components. You need the first item to remember Lexy. Get missing persons at 300. Save your game and make sure coding and missing persons are at 600.
When you talk to Fexa on night 7, meet her in a VIP room and speak her true name and have Lexy appear. Boop the snoot at your own risk. End the night with missing persons at 700. Research coding afterwards to get to 700.
Night 8 is when Marie first appears, so free Chiku on this night. End night 8 with coding at 900. After some fun time with Zero and Lexy, research coding to max and focus on missing persons from now on.
Free Frenni on the 9th night and get missing persons to 800. Continue with missing persons at 900 before night 10 begins. You'll be prompted to attempt a ritual, choose to hold off.
You'll get a USB on the 10th night, after you plug it in, max out missing persons and you'll remember Marie's true name. Again, hold off on the ritual. From this point, you can research paranormal again.
Have Bonfie help you out on night 11 then speak her true name when prompted. Get paranormal to 500 after the night and you'll "milk" Zero for the next part of the ritual. Paranormal should be at 650 before beginning night 12.
Meet with Frenni in the VIP room where you'll encounter Marie. Since you know her name, you'll free her, otherwise she'll kill you and end your run. Afterwards, get soul binding materials, and body armor. The remaining items are optional, but buy one of them if you choose. Choose to attempt the ritual on night 13.
If you did it correctly, you'll get the true ending. Hope this guide was helpful. Once again, sorry for the long read.
Edit: fixed grammar
