My girlfriend went back to college early, called me just now, and said she was approached by a man dressed in black with something in his hand like a butterfly knife. The man let out a creepy 'hey' and my girlfriend ran into her house (where her roommates and a couple guys were hanging out). Luckily, nothing happened, but I am worried. Other than self defense classes, where can one buy pepper spray or mace? What other concelable self defense items are available?