I'd give 7/10
It's just the typical MLs falling in love with FL for no reason,
and the bodyguard is kinda pathetic trying to touch the FL every chance he get , she's clearly not interested in him.
For similar plot "I Saw the Future With the Killer Grand Duke" is way better.
Still i like that the misunderstandings get resolved quickly. And the lovey-dovey moments are great !