He’s called “Big Luther” because he’s really tall (at least 6’ 8”).
I don’t like this appointment, but not because of Luther’s political leanings, which are pretty conservative. It’s because Bentley is on the cusp of being investigated for unauthorized gifts and undue influence over governmental affairs by his “alleged” mistress. It’s been said that Strange is about to launch an investigation of Bentley. So to nip the investigation in the bud, Bentley appoints Big Luther to the vacant Senate seat. Crooked business.
Bentley is doing this to stop the investigation.