Magic school has 3-4 endings.
1. Getting out. - Only this one is that "walkthrough"
2. Dumpster in Dark magic room after failing to summon armor
(2a. Dumpster after getting armor but losing vs Beryl)
3. Eternal Doll with Ross surviving, you have to NOT resist killing Dragondude, then get your wits and protect Ross from Old Principal (I think)
Hardest is #3 - because the affection points with Dragondude .......... well, if anyone knows how to best ignore the guy to get his value to 0 or so, I think the 6th Beryl visit must not "fail" but even with Affection 28 it fails
I also think Dragondude must NOT appear in SoulSpace
AFAIK one needs this ending (Magic Bad End B) simply because it is an Ending - and one needs ALL "non-True" endings first or Wolfie keeps winning in Sky God Castle
I for one also keep getting "Pervert Ghost Updated" after "Good" end (#1) but I never even found the quest, I ghostscared both in kitchen and in Mind Magic classroom but no new targets appeared, also the dude who volunteers for Ghost doesn't appear
Funny sidenote: My Endings List in Game shows 2x Magic Bad End A (less than 5000 or losing) - that's why I am unsure about the real reqs for B