Scifi/fantasy book where 3 girls take a summer job on a farm and encounter a bat-winged humanoid

Question

I am pretty sure I can give accurate character names and a summary of the plot.

• Scifi/fantasy/Romance;
• Published in the early 2000's;
• 3 books total at the time;
• 2nd book had the word "planet" in the title, with a blue vampire alien and a human girl standing in each other's arms.

Characters

• Main vampire alien named Novak;
• Main female human named Riley;
• Novak's best friend is named Jax;
• Riley's best friends and college roommates are Lauren and Angie;
• Novak's younger brother was a sort of amateur scientist/botanist;
• Novak has an evil uncle;
• Novak's mother and father are still living;
• Novak was betrothed to a vampire/alien named Serphina;
• Two sisters that are queens on their own planet are fighting against each other.

Plot
3 college girls get a summer job on a farm, working in the fields. One night the dog brings a large bat, wing full (person) size into the farm house. The girls continue to investigate, they look over the neighbor's fence/wall and see normal handsome men. The three girls somehow hear a loud noise and go to investigate and are captured by the strange men. Riley finds herself on a spaceship with Novak, and her roommates take the other ship to follow Riley and bring her back to Earth. The whole story is the three girls trying to get home to Earth.

Answer 1

This is Hotbloods by Bella Forrest.

One last adventure. That's all Riley wants before heading off to college and parting ways with her two best friends [Lauren and Angie]. Spending their last summer together on a Texas farm in the middle of nowhere isn't quite as exciting as they'd planned...

Every oddity seems connected to their strange--and alarmingly attractive--new neighbors, led by the stormy-eyed Navan. For reasons she can't explain, Riley feels drawn to him and the story of his past.