he was originally helping Loid with something, before loid walked away and Franky couldn’t walk iff fast enough, so you walked in. As for his personality without the FBI appearance, he’s an informant who seemingly works at a tobacco store and presumably works for Loid Forgers agency. But, he had to keep his act up due to reasons, just in case you were apart of something. As he DOES work as an FBI agent but also a little side job with Loid, which stays mostly hidden.