Cassandra's Castle

What Cassandra doesn't know is that she has become a pawn, entwined in a dark and dangerous rebellion. Her initial alliance with Valerio turns out to be more sinister than what she expected.

She meets the royal family and before she can fully understand her mistake, it's too late.

Original & Compelling YA Fantasy from D. L. Gardner read the review at Book Viral

Seventeen years after Ian left the Realm, his daughter, Cassandra Wilson, discovers a portal accessible through her cell phone. Thrilled that she gets a chance at exploring the world her father told her about as a child, she defies her friends and goes in. When Cassie finds out from the grumpy old wizard Silvio that she's a princess, the news comes as a shock, and Cassandra has no idea how to handle it.

At least, not until she meets with Valerio, the handsome commanding officer of Alisubbo

It's Valerio that persuades Cassie to join his revolution to free the people of the city that he claims has long been suffering under the tyranny of King Chavez. Only a foreign princess can deliver their much needed appeal to the throne in hopes that a peaceful compromise will be had.

With hands stained in blood, the burden of a nation is on Cassie's shoulders. Her only redemption is to convince the reluctant heir to champion his father's throne.