Most Helpful Guy
He might not want to approach you so soon after a break up, if he knows. Some guys don't like being a rebound.
Most Helpful Girl
This is some pretty vague information. Not every guy who calls a girl pretty wants a relationship/dating. It's pretty superficial basing your dating chances off of that.
Try actually getting to know him first. Be friends, make plans to go out for lunch on your work break sometime :)