Helen was Claymore No. 22 of the 135th generation in the Organization. Helen is often hot tempered and aggressive, humorous and rebellious at times who can appear to be a troublemaker, as Deneve notes. She seems to have a large appetite (for a Claymore at least) and can often be seen eating an apple. She's also the only Claymore seen eating and drinking for pleasure. Helen has short hair, but unlike Clare's pageboy, Helen's is parted down the middle with one side tucked behind her ear. She wears black pieces of armor on her arms and legs to allow her to stretch her limbs. Helen is usually seen smiling, smirking or snickering.

When Helen was in the Organization, Helen wore a regulation uniform, in addition to "extenders." These were highly durable, extremely flexible, portions of fabric that provided protection over her arms. These allowed her coverage while using her special attack. This is similar to the material of Alicia's black uniform. Helen has a unique demeanour compared to the other Claymores. She can be bold, overbearing and brash. She is similar to Noel in these aspects. However, she is also one of the most optimistic and cheerful of the Claymores and tries to enjoy life as much as she possibly can, which explains her unusually large appetite. She makes many attempts to lighten up the "doom and gloom" attitude of her fellow warriors, despite the many grim situations they get themselves into, such as the Northern Campaign.