"Welcome to the worst day of your lives!" - Negative Numbuh 86
Negative Numbuh 86 is the negative-world counterpart to Fanny Fulbright/Numbuh 86 of the Kids Next Door.
Unlike the unpleasant, bossy, rude, somewhat selfish Numbuh 86, Negative 86 is kind, polite, affable, pleasant, friendly and helpful, although she is very shy like Negative Numbuh 1. She was formerly the adviser to Negative Numbuh 4, before he was kicked out of the Destructively Nefarious Kids organization by Eizzil Enived.
When the DNK made plans to kidnap kids from the positive universe, they kidnapped and later chased Positive Numbuh 1 and his girlfriend Lizzie Devine. Eventually, their chase lead to the trailer of the Little Traitor Dudes For Children's Defense. Negative 86 cornered the two runaways with an entire DNK brigade backing her. However, Positive 1 and Lizzie pretended to be their Negaverse counterparts, and tricked her into thinking that they are on a mission for the Supreme DNK Leader.
After Negative 4 had Numbuhs 1, 2, 3, and 5 sent to the Broccoli Mines, Negative Numbuh 86 rescued them, acting on Numbuh 1's advice that she was "too good for this" (the DNK's evil plans of domination).
In the end, she told the DNK, she was sick of pretending the DNK were protecting others, and that she wanted to pretend she was a pretty princess (which Numbuh 2 commented on, saying that Negative Numbuh 86 "is definitely Numbuh 86's opposite"). The rest of the DNK decided to follow her example and live their dreams and turned on Negative 4. After his defeat, Negative 86 banished Negative 4 to his broccoli mines before vowing to reform the DNK and making their world a better place for both kids and adults.
- Her real name might be Enicnarf "Ynnaf" Thgirbluf, though this was unknown.
- Her looks are visibly different from that of Numbuh 86.