An Advena Avis immortal and only woman aboard the ship. She saved her share of the immortality elixir and drank it a few years after the rest of the passengers. After her lover, Gretto, was devoured by Szilard, she decided to devote her life to seeking revenge for his death. By the 2000s she had reunited with Maiza and Czes and joined them on their quest to find the rest of the immortals.
The Head Butler for the king. Teufel is a demon with soul manipulator magic; his magic allows him to manipulate souls of others. However his power causes the side effect of stiff shoulders resulting him to refuse usage of his magic if not given any proper shoulder treatment. His stiff shoulders do not necessarily stop him from using his magic, it's just he can't lift his shoulders up, and so cannot move his arms.
The Nisepanda is not actually a panda, but a giraffe.
The title character of the story, Zwei was a perfectly ordinary tourist from Japan, before witnessing an Inferno assassination in America and being kidnapped. He was able to elude his pursuers long enough for them to realize he had a natural survival instinct that was perfect for an assassin. He had his memory erased through a combination of drug and hypnotherapy. The name Zwei is simply a code name to show he is the second experimental assassin created by Scythe Master. Through Claudia, one of the three top executives of Inferno, Zwei is able to learn his true identity as Azuma Reiji. At the end, when Reiji and Eren finally set out to find her past and end up in Mongolia in a field of Oxytropis flowers, an unidentified assassin kills Reiji with a silenced gun, and he collapses silently to the ground. Ein then appears to commit suicide by eating a leaf of the poisonous flower. It is hinted in the leadup to his death that Reiji saw his end coming, and accepted it, having considered his final task complete. His name means "two" in German. (Source: Wikipedia)
Szilard's homunculus, although not his first creation. She was created as his subordinate, and is supposed to have no thoughts or emotion when executing his commands; recently, however, she has been gaining more human emotions, as well as independent thought. Eventually, she helps Firo by giving him the necessary knowledge to destroy Szilard and after over fifty years of courtship the two marry. (Source: Wikipedia)