This personality type can get somewhat obsessive with keeping their money in. Feverishly turning all the lights off and never splitting the bills with friends (unless the Frugal has a higher bill and would benefit from the split, which rarely happens due to their attention to price) they tend to over-worry about losing their money in any way.
Not eager to help others financially nor being fond of giving gifts, they are often perceived as penny-pinchers. In savings and investments, this type would forgo potential return for safety (e.g., keeping cash under the mattress).
The Frugal longs the feeling of security and control and may have other emotional needs which they try to compensate for by being overly frugal. If you spot the behaviors of frugal, work on your emotional body and try to get yourself exposed to a bit more of a risk, gradually.