Cyril is friendly in an at-arms-distance sort of way to nearly everyone he meets, as a result of being raised to basically become a saint after his death. However the same training and raising that led to his friendliness has led him to become wary of depending on others too much, as he has been raised to think that he is supposed to be the infallible rock that everyone else is counting on. Thus he is one of those people who when you meet him you can't help but like but when he leaves you realize you know next to nothing about him.
One thing people who know him really well or people who have known him since he was a child know is that he has a very goofy sense of humor. He keeps it under wraps pretty well, but at a moment's notice when he doesn't have his guard up he will laugh in hysterics at the silliest of jokes. He especially loves puns.