As opposed to a trivia question, because I do not actually know the answer here. Did we ever see any other random Enterprise crew who were full commanders other than the security chief in "Devil in the Dark"?
In "Mirror Mirror" Marlena says something like, "Commander Kenner will take me temporarily, he's made that quite clear." That might have been a pun, since Kenner was a big toy company at the time, and Marlena was a plaything.
That Czech website with the transcripts made from the DVD subtitles gives the name as "Kenno." But what do they kenno?
Were you talking about Giotto in Devil in the Dark? He was a Lt. Commander, not a full commander. Excert: Kirk: Mister Spock, have Lieutenant Commander Giotto assemble the security troops and arm them with phaser number two. Later: KIRK: (on communicator) Lieutenant Commander Giotto. GIOTTO: (on communicator) Giotto here, Captain. Are you all right? http://en.memory-alpha.org/wiki/Giotto
Yeah, it was Kenner. I just found it in the description of "Mirror, Mirror" Act 3 on the memory-alpha wiki.
Commander Kenner, or Commander Kennser? I think Kennser and Marlena Moreau would make for a cute couple. (now get the image of them having freaky sex out of your brain)