I believe Killian yelled "Liam!" when his brother collapsed at the end there.

One of the books is actually called The Color of Her Panties. Although I loved the series as a kid, that one did sort of raise a red flag even then.

There was a computer game based on the book Demons Don't Dream. Not sure if it shared the same name.

I read these in middle school, and adored them at the time. A few years ago I re-read the first 2 or 3 and came to the same conclusions as Jason. It was kind of shocking.