Boldir is a calm and collected individual, not prone to unexpected bursts of emotion. Upon meeting her, the player is instantly soothed by her presence as they feel no urge to prove themselves worthy of friendship. Boldir appears to be completely at ease with her place in the universe, for she doesn't seem to mind her worth (or lack of thereof) in regards to her existence. When she's on the brink of death in one of her bad endings, she isn't particularly upset with the notion of ceasing to live and breathe. 

She also appears to be incredibly well-read, given her ability to understand the details regarding destiny and causality. She casually debates the two concepts while on a stroll with the player, even though the player has some difficulty digesting the information she's dishing out. This might be due to her vagueness when conversing with the player, as she often asks rhetorical questions and gives thought-provoking statements. As it were, it can be deduced that she's well-versed in philosophy.

Boldir is noted to be a very cautious individual: after leading the player out of the cafe, she constantly checks her surroundings and takes numerous detours as though trying to shake off a stalker.

She is noted to speak in a sort of stage whisper.