Jake Lockley is an alter of the DID System that is
often called the " Moon Knight System" or the "Moon System".
Jake Lockley, Marc Spector and
Steven Grant (depending on which comic or if we're talking about the TV show "Moon Knight", Mr. Knight and Moon Knight too) are members of that system.
In the comics Jake Lockley is known for his
friendship with Gena Landers and Bertrand Crawley, but even more so for his flat cap and fake moustache.
In the TV show, Jake Lockley has made an appearance in the post-credit scene. It is also known that it was Jake who was trapped in the other sarcophagus in the end of episode 4.
It was also Jake Lockley in the beginning of episode 5 during the "
therapy session" with "Doctor" Harrow and the one who said "And as tempting it is to accept your diagnosis, Doc..." in the end of episode 6.
Jake Lockley was fronting several times in episode 3 and episode 6.
Jake Lockley is not evil. She will simply do anything to protect Steven and Marc and make sure they're safe.