Sounds like you got the “bad” ending.
Viewing post in Homecoming ~Morenatsu Revisited~ comments
Every character has a good ending and at least one bad ending (Shin has two bad endings, though not as bad as in the original Morenatsu). Since you got the bad ending, you should have unlocked the route guide for Kyouji. If you go into the gallery, and select route guides, you should be able to see the guide to get his good ending (which requires a perfect playthrough).