when someone is afraid to do an action or " something" the original term is "scary cat" also known as "pussy" and not everyone has the right to use that word and some people might find it offensive to use so the term should be " Cheese Cracker".
chad: hey bro let's go rob this old lady Juan: man I don't know, it just doesn't seem right
Chad: don't be a CHEESE CRACKER !
John was such a workaholic that he had a 9-5 job and a second job he worked at nights. Each day John would multi-clock in to work. His mum said "John why do you work so hard? You're such a multi-clocker!"