I'm glad you liked it :3
Unfortunately though, any answers I give to your questions would be guesswork really, as unlike my other projects which are all original stories that I've written featuring original characters, this project in particular is actually just a fandub of an old Japanese audio drama CD series, so the story and characters aren't mine, I just localised the scenario and turned it into a VN :(
You can find the official page for the original Japanese version here if you wanna take a peek :3 http://www.hobirecords.com/yandere/
I listened to all of the CDs many years ago, and I've wanted to make a fandub for a while, so yandere jam was the perfect opportunity for me to localise the scripts and make it into a VN :3
I wanted to stay as true to the original story + characters as possible. I'd love to be able to tell you that answers to your questions arrive in the other volumes, but sadly, each volume is a completely different story/scenario with brand new characters x3
I will say that all of the scenarios in the series have moments and characters that are pretty farfetched and unbelievable, haha. Such as the fact that neither Atsushi/Aoi or Kakeru/Kasumi's parents seem to have even the slightest idea of what's going on! All the characters' behaviour escalates so quickly since they're only short CDs, and they all get away with behaving like lunatics, seemingly without any sort of repercussions! There are plot holes aplenty x3 But I still found the series to be a lot of fun when not taken too seriously.
Sorry I can't be more helpful >.<