Hilda Dietrich (ヒルダ･ディートリッヒ Hiruda Dītorihhi) is a teenage girl who lives on the island of Growerth with her parents and older brother Michael Dietrich and her parents. Formerly human, she is turned in 2005 by Dimguil Sunford after Juna Riebeluka carves out her heart.
While Dimguil has returned Hilda's heart to her, her heart is occasionally subjugated from time to time and thus throws her into a 'death-like' state. When she is in this state, no one – not even Relic von Waldstein – can affect her without a mysterious power blocking their efforts.
On the advice of The Doctor, Relic and Hilda have decided to travel to Japan in search of the Kumanobe Clan – a mysterious clan of vampires who may know a method through which turned vampires may regain their humanity.
Hilda is a teenager with shoulder-length brown hair and brown eyes. Once she is turned, she gains fangs in the vein of other humanoid vampires. Like her brother, her casual attire of jeans and simple shirts contrast the fancier attire of the Waldstein siblings.
Hilda is kind and patient, considerate of others and like her brother is utterly accepting of all those who are not human. Unlike Michael, she does not possess an encompassing lack of prejudice: having witnessed firsthand how her parents have lashed out in fear at vampirekind, she has gravitated more toward the Night and developed a slight bias against her fellow humans as a consequence.
However, as a human Hilda despises her own weaknesses as an individual (or 'individual human') even more than she dislikes humanity overall, believing that her inability to defend herself makes her an increasing burden to Relic. At her lowest point, she briefly wonders if her attraction to Relic was simply borne out of wanting to spite her parents – though she concludes that even if that were the case, she still deeply loves him.
To be added.