Crowley must really trust you because rarely will you see a snake let you stroke and caress it's head like that, most BP's usually jerk back when you get near it's head. Pretty amazing the bond you two have. It shows you have gained his trust and as you say it must have took a quite a bit of handling. They like the warmth we provide.
Due to the germs they can carry ( like salmonella) I always wash with soap and water before and after handling. and use a disinfect wipe to wipe myself down with after handling.