Blackquill is a family name that may refer to:
- Simon Blackquill, a prosecuting attorney and former prison inmate.
- "Blackquill" is a combination of "black" (dark colors being prominent in Simon's character design) and "quill" (a writing implement made from the molted flight feather of a bird).
- The Japanese equivalent, "Yuugami" (夕神) is possibly a play on the word "yugami" (歪み), which means "a warp/distortion". When taking the meaning of the kanji into consideration, "Yuugami" literally means "evening god".