3 Books Found

Based on your description:

"A girl's parents were adventurers and her dad is kidnapped. The parents had discovered an island before she was born where there is a genetically superior human civilization that lives longer and is stronger, etc. The antagonist(s) wear masks and the main one is a cop. She falls in love with a chimera, a man who has DNA from both the regular human race and this advanced race. At the end, they travel to the island. "