The text below is from Umberto Eco's book, The Name of the Rose.
For that matter, my attention immediately turned to the person of whom I had heard most talk recently: Bernard Gui, as the French called him, or Bernardo Guidoni or Bernardo Guido, as he was called elsewhere.
He was a Dominican of about seventy, slender and erect. I was struck by his gray eyes, capable of staring without any expression; I was to see them often flash with ambiguous light, shrewd both in concealing thoughts and passions and in deliberately conveying them.
In the general exchange of greetings, he was not affectionate or cordial like the others, but always and just barely polite. When he saw Ubertino, whom he already knew, he was very deferential, but stared at him in a way that gave me an uneasy shudder. When he greeted Michael of Cesena, his smile was hard to decipher, and he murmured without warmth, “You have been awaited there for some time,” a sentence in which I was unable to catch either a hint of eagerness or a shadow of irony, either an injunction or, for that matter, a suggestion of interest. He met William, and when he learned who he was, he looked at him with polite hostility: not because his face betrayed his secret feelings, I was sure of that (even while I was unsure that he harbored any feelings at all), but because he certainly wanted William to feel he was hostile. William returned his hostility, smiling at him with exaggerated cordiality and saying, “For some time I have been wanting to meet a man whose fame has been a lesson to me and an admonition for many important decisions that have inspired my life.” Certainly words of praise, almost of flattery, for anyone who did not know, as Bernard did know well, that one of the most important decisions in William’s life had been to abandon the position of inquisitor. I derived the impression that, if William would gladly have seen Bernard in some imperial dungeon, Bernard certainly would have been pleased to see William suddenly seized by accidental and immediate death; and since Bernard to those days had men-at-arms under his command, I feared for my good master’s life.
Historical material relevant to the actual figure:
https://en.wikipedia.org/wiki/Bernard_Gui
https://sourcebooks.web.fordham.edu/source/bernardgui-inq.asp
https://en.wikipedia.org/wiki/Bernard_Gui
https://sourcebooks.web.fordham.edu/source/bernardgui-inq.asp
