One of the most interesting tropes that pop up in anime are half-human anime characters. What that means exactly can vary from show to show, but here's the basic run-down: hybrid anime characters possess both human DNA and DNA from another species. In most cases, the non-human species is a mythical one, like demons, elves or angels. Half-human hybrids are typically born to one human parent and one non-human parent, but some are fused with another species later in life, often violently. Half-human characters are typically found in demon anime and shounen anime.
Being a hybrid can mean enhanced magical and physical abilities, like it does for Tokyo Ghoul's Kaneki Ken and Gohan from DBZ. In some cases, like with Gojyo from Saiyuki, it means facing discrimination and functions as an allegory to real-world racism. In other cases, like with Eina Tulle in Is It Wrong to Try to Pick Up Girls in a Dungeon?, the character's hybrid nature has basically no impact on anything. Take a look at some of the best half-human hybrid characters and vote up your favorite.
Rin Okumura, the protagonist of Blue Exorcist, is the son of a human woman named Yuri Egin, and the lord of all demons, Satan. Yuri died while giving birth to Rin and his fraternal twin brother, Yukio. Shiro Fujimoto, who had been ordered by Yuri's father to kill her and her devil babies, ends up taking pity on the newborn babies and letting them live.
Instead of killing them, he seals their demonic powers and raises them as normal humans. Despite his alleged "full humanity," Rin's headstrong behavior still gets him labeled "a demon child" in school. Eventually, Rin is unable to continue living a "normal" life, and has to start using his powers. While there are plenty of stories about the so-called anti-Christ, few of such characters exist in anime, and even fewer are as complex a character as Rin Okumura.
Inuyasha is one of the most famous examples of a half-human, half-something else hybrid. Inuyasha was born to a human mother and a dog yokai father. This results in some serious problems with his full yokai older brother, Sesshoumaru. Sesshoumaru looks down on Inuyasha for his "tainted" heritage and resents him because their father gives Inuyasha a more powerful sword.
While some of the rancor is due to personal family issues, some of it is fantasy-world racism. Inuyasha's yokai features and abilities actually disappear during the new moon, sort of like a werewolf in reverse.
Tokyo Ghoul's Ken Kaneki started out entirely human, but that changed after ghoul organs were non-consensually transplanted into his body. He became a "one-eyed ghoul," or a half-human, half-ghoul. This grants him extraordinary powers and an almost mythical status within the ghoul community. However, it also means he has to get used to the physical and moral implications of his newfound hunger for human flesh.
It's difficult to chose just one half-human hybrid from Dragon Ball Z. There's Trunks, Bulla, Gohan, Marron - the list goes on. Gohan, a half-human, half-Saiyan, deserves special mention for a few reasons. First of all, he's the only half-human, half-Saiyan to display significantly greater power than his full-Saiyan equivalents. That's just cool.
Second, we get to see how him navigate completely different expectations from his human mother and Saiyan father. Chichi, his mother, really just wants him to do well in school and get a good night's sleep. Goku, his father, wants him to use his strength to help defend the Earth from its enemies.