Responsible, self-sufficient, and determined...but also distractible, tense, and hurried.

Generally speaking, Heidi is quite sociable and friendly to others; even with her mutism, she can still maintain a conversation by sign language and an interpreter for a very long time due to her knowledge of many, many topics she deems interesting. As a result, she is well-loved by her adoptive family and friends, and she has even found it to be relatively easy to make new friends as well.

Despite her casual demeanor, though, she always seems a bit on edge for some reason. Even if she doesn't remember why exactly, there's always a lingering sense of danger that only she feels, leading her to keep a hidden weapon (mainly her gloves) on her person regardless of the situation. Maybe it's best not to pry on such a thing for now.