Alright, so I was searching for a Koyanagi's TRUE ending guide but coudn't find a single one in english that worked for me. This is in japanese but workes!! (tested) and I will provide a rough traslation.
Link to forum post, it has every route I think:
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And the Koyanagi route:
> 1st day: Koyanagi
> 2nd day: Uehara's work → Detour → Park → Unforgiven → Pain → single whip
> 3rd day: Angry → Market → Kugai → Hope → Shame → Park
> 4th day: Sartori → Park → Kugai → Shame → Sartori → Finger → interested
> 5th day: Park → Park → Kugai → Look → Go outside → Humiliation → Sartori → Medicine
> 6th day: Park → Park → Kugai → Shame → Park → Let him suck it
> 7th day: Koyanagi
> 8th day: Kugai → Park → Self-introduction → he wouldn't want that
> 9th day: Sartori → Park → Kugai → Give water → Sartori
> 10th day: Market → part of the job → Kugai → Sartori
> 11th day: Park → Park → Kugai → Urination → Anus → Park <Reminiscence start>
> 12th day : Park → Kugai → Anus → Park
> 13th day: Kugai → Dirty → Park
> 14th day: Park → Market → Tonight's snack → Kugai → Gentle → House → Wait → In pocket
> 15th day: Kugai → Immediately order → (1-1-1) → House → Give it to me
> 16th day: Park → Market → Kugai → Hurry → Down → Hurt(there was no choice here for me so idk) → Park
> 17th day: Park → Be strong → Market → Kugai → Forgive him → Park
> 18th day: Residential area → (2) → Kugai → Park
> 19th day: Sartori → shouldn't Leave → Kugai → Penis → Park
> 20th day: Park → challenge → (1-1-2-1 ) → Kugai → Long whip → Tightening → Park
> 21st day: Park → Park → Kugai → Koyanagi → Park
> 22nd day: Sartori → Sartori → 2 → Kugai → Koyanagi → Park
> 23rd day: Market → continue day → Market → Kugai → Don't use anything → Good job → Park
> 24th day: Sartori → Sartori → Kugai → Love → Sartori
> 25th day: Sartori → Sartori → House → Koyanagi → Sartori
> 26th day: Park → Park → Park → Park <Tasting>
> Day 27: Sartori → Sartori → Sartori → Sartori
> Day 28: Park → Park → Park → Park
> Day 29: Market → Market → Market → Market
> Day 30: With Koyanagi →To the outer corridor
numbered steps means that you choose that step from the list e.g.:day 20 step 3 during the quiz the 1st answer is the 1st row one, the 2nd answer is again the 1st row the 3rd is the 2nd row and the last answer is the 1st row.
btw house means residential sorry