Britney Spears' Ex-Bodyguard -- I'm a GHOST-HUNTER Now!

First there was Scooby Doo ... then came Peter Venkman ... and now, there's another hero protecting humanity from the paranormal -- Britney Spears' former bodyguard.

His name is Fernando Flores -- the same guy who once sued Brit Brit for sexual harassment, claiming she exposed her genitals to him while he was on the job. The case eventually settled out of court.

Flores -- who says he's in the process of joining the LAPD -- tells TMZ, "I'm not proud of what happened with Britney, but it's opened the doors to where I am now."

And where he is now ... is ghost hunting with a crew called the "Orange County Paranormal Project" ... documenting incidents from the spirit world.

FF hasn't been in the specter business for long, but swears he's already captured some crazy stuff -- including "some pretty creepy voices."