For those of you who already had to read the book for school, you can skip this part.
Anyway, Jekyll & Hyde was a novel by Robert Louis Stevenson which was about man vs. his dark side. One moment he goes from perfectly average guy to complete and utter psychopath.
In SMMH, he's more of both. He's second in command to Ramses and in normal time, he's overachieving at school.