Heinkel has neck-length, straw-colored hair, and grey-green eyes. She dresses in the priest uniform of the Iscariot Organization. Heinkel is usually seen with two pistols as a preferred weapon.
Heinkel makes a couple small appearances in the Hellsing: Ultimate OVA IV, as a non-speaking character who shoots a corrupt priest when Maxwell instructs her to. Latter she aims a pistol at Schrödinger when he appears suddenly at the Hellsing-Vatican meeting with the Queen of England.
She often acts as a bodyguard for Enrico Maxwell along with Yumie, she is later seen among the brigade of Catholic priests sent to apprehend Integra under Father Anderson's leadership. In Chapter 74, she is shot in by The Captain. The bullet entered through her left cheek, and exited through the right, and severely damaged the right side of her face. Heinkel is bewildered as the Captain gestures to her with his head, which she interprets as "Stay out of the way". He tosses her a first-aid kit, and Heinkel realizes that the Captain spared her life when he could have easily killed her. After seeing Yumie's remains, a bandaged and enraged Heinkel swears revenge on Walter, and takes a sniper rifle from the small group of remaining Iscariot priests. While Walter is distracted by Alucard's remains, Heinkel shoots him through the chest with her sniper rifle. However, it fails, and Walter cuts off Heinkel's arm and leg, who was rescued by the Iscariot.
In the final chapter, Heinkel appears as a silhouette next to Makube and an unnamed younger Iscariot 30 years later. Heinkel's face still has severe scarring from the wound inflicted by the Captain. She appears to have all four limbs once more, though it is not clear if her severed arm and leg were reattached or replaced by prosthetics. It is unknown if Heinkel still uses pistols. The younger Iscariot suggests trying to destroy Hellsing right then and there and Heinkel calls him a "blind fool," but agrees it would be possible take out at least half of the Round Table at the certain cost of their own lives. Makube refuses the idea and it's revealed, that as of now, the Vatican, and presumably the Iscariot Organization, is too weak after the 9th Crusade, and that the next crusade will have to take place at least some centuries from now.
- Remarks made by Kouta Hirano in a December 2005 issue of "Puff" magazine, in which he was interviewed about the upcoming Hellsing OVA series and Hellsing in general, have shed new insight into Heinkel and her androgynous appearance.
- Kouta Hirano stated in an interview in the Hellsing Guidebook that Heinkel is "neither male or female" and said that "hermaphroditism is something I had always wanted to feature in my work." Though, it is unknown if his words can be taken literally here as he joked about several other things.
- Heinkel's reaction to Yumie's death and her emotionally-charged actions afterward imply some sort of close relationship, platonic or amorous. Having grown up with her in the same orphanage, it's likely that it's a close friendship or possibly a sisterly bond that fuels Heinkel's lust for revenge.
- It is possible that she is of German origin, given her name. Heinkel was a World War II aviation company, which produced, among others, Heinkel He-111 used during the battle of Great Britain. Her last name, Wulf, bears some resemblance to the German word "Wolf" the wolf. The fact she may be a German Catholic mean she may have originated from Southern Germany.
- A very similar character by the same name is featured in one of Kouta Hirano's previous manga, Crossfire. However, it was actually revealed that Kouta changed it to non-canon due to the fact that Enrico Maxwell looked too much like Integra.
- Heinkel's prototype was in Daidojin Monogatari along with Walter.
- Her appearance which looks much like a boy might be a reference to Joan of Arc.
- There has been much speculation regarding Heinkel and how she may have become a regenerator during the time skip to replace Anderson.
- The looks exchanged by Heinkel and Seras Victoria at the end of the manga and the OVA have led to speculation they may have developed a rivalry similar to Anderson and Alucard.
- The slides on Heinkel's guns are engraved with words from the Latin chant "Dies Irae," which fittingly describes Judgment Day.