A decade or more ago, I remember reading that (anonymous) workers at the SCOTUS said that Thomas was the nicest of the justices. IIRC, some of them considered him the ONLY nice justice.
I personally know a few former law clerks of his, and they have all said the same thing. He speaks with most of them regularly.
I’ve also heard from the former clerk of the Supreme Court that Thomas always wins the Court’s NCAA bracket.