F. D. Stewart 
The Livingston Gatekeeper Meets Hannah, the Mistress [EPUB ebook] 

An altercation may have caused a shift in the realm for the group of college friends as they enter in a different dimension with no warning. With the return of Peter from the Pegasus World, nothing seems to change. Everything is more chaotic now more than ever. What they thought would put everything back to normal is far from the truth and accepting their identity comes with a price. Now this group of college friends must find a solution to save their world and themselves by battling in other realms. They will have to agree or fight to their death. There is a saying, “Evil is present, but good conquerors all.” But at this level, evil seems to be winning.