Nabiki is the middle of the three Tendo sisters and is a second year student at Furinkan High School. When Soun informed his daughter’s that he engaged them to his friends son Ranma Saotome only for him to arrive with a panda she dragged him to the dojo to demand an explanation. However upon finding out that he was catatonic she left him there in disgust.
Nabiki was once again disgusted after Genma explained his version of what happened. Seeing Ranma sitting their oblivious to his surroundings, as the others badmouthed him openly Nabiki felt a little remorse at having lashed out at him for something that probably wasn't his fault. Wanting to get away from her younger sister, who was questioning Genma about his knowledge in martial arts with an eager smile on her face. Nabiki helped Kasumi lead Ranma to his room.
Months passed in a relatively monotonous way. Akane trained with Genma and Soun, who regained his passion for the Art with the arrival of his friend and his daughter's dedication. Akane's skill in the Saotome branch of the Anything Goes was very limited due to her temper and tendency to use strength instead of speed, but she advanced pretty well on the Tendo branch. Soun and Genma sparred everyday and congratulated themselves for starting a class in the afternoons. Soun, Akane and Genma ignored Ranma's existence as best as they could. Nabiki returned to her routine after the first two weeks. She gave up on Ranma and now simply ignored him. Not that she didn't care, but she felt it was a weakness on her part to feel for a lost cause.
After Ranma came out and it appeared that he had attacked Kasumi while the others searched the streets to make the pigtailed man pay Nabiki helped her older sister up to her room. Vowing that she would make Ranma pay for what he did. The next day after calming down and realizing that given Ranma’s strength her sister wouldn’t be here if he had attacked her she confronted Kasumi and got her to admit what really happened.
Since Kasumi didn’t want there to fights within the family Nabiki agreed not to tell her father what happened. She later found him in the park and after talking to him Nabiki began to wonder what was wrong with Kasumi and Ranma as they were both trying to make sure the other wasn't hurt and ended up blaming themselves for others' doing. Giving up on it she took him back to the dojo to get his pack. However much to her anger after getting his pack Ranma just left as soon as Kasumi told her she ran out looking for the pigtailed man.
She caught up to him just as he was about to fight Dr Tofu. Knowing what her father must have told Tofu but not wanting to repeat it while Ranma was present she tried to explain that Kasumi was actually saved by Ranma. While she didn’t get him to calm down completely he did leave.
Nabiki quickly noticed that Hinako no longer needed to drain people to keep her adult form as well as her Blue Green Eyes and confronted her after school. While she didn’t tell Nabiki what had transpired between the two she did take her home to see him.
Tofu eventually informed Soun that Nabiki was helping Ranma making Soun convinced that that Ranma was somehow forcing her. By this point Nabiki was getting tired of Kasumi’s passive nature as all it would do is end up getting Akane and their father killed is she didn’t tell the truth. While she didn’t like calling Kasumi out like that after hearing what Ranma did to some Black Dragon members she felt it was for the best. Their fight was interrupted by Shampoo tracking Genma down.
The same day that Aeris was enrolled in Furinkan high it was attacked by Sephiroth and Nabiki was nearly killed. Luckily Ranma was able to stop him and heal her wounds. Since school was canceled because of the attack Nabiki attempt to go to Hinako’s place to demand answers to what had happened only to catch trying to trail her. Knowing that if Tofu saw her with Ranma her father would be on her case again she just went home. Finding Kasumi drinking tea with Shampoo she explained what happened when they were interrupted by Soun and Genma. By this point Nabiki had lost almost all respect for her father so when Soun demanded to know the wear abouts of Ranma she just snapped to do what. Even when he slap her and demanded that she respect him in his house she reminded him that the house was there because of her. Kasumi seeing this realized that it was finally time to come cleam and had Shampoo take Nabiki to her room.