This looks like pepper spray or mace, but instead sprays strong garlic over an attacker. This has minimal effect on a human being beyond ruining his chances of getting a date.
Roll Dexterity + Gun Fu -2. if an attacker gets 3 or more success against a human she has hit him in the eyes and the Success Levels minus 2 is the number of rounds that he is incapacitated. less than 3 successes then she has just critically wounded his chance of getting a date that evening. Hey look at that, rules for a Pepper Spray at the same time!
If the attacker is a vampire, then just spraying their clothes and skin is enough to ruin their night. Just one Success Level will inflict a -2 penalty on all their actions as the garlic irritates their skin and even the smell disgusts and distracts them. If you get 3 or more Success levels on an attack against a vamp then they are incapacitated for one round. The -2 penalty remains until the vampire immerses itself in water.
A Garlic Spray only has one use before it is emptied and only has a range of 3 yds.