Lisa Nanase (七瀬 リサ Nanase Lisa) was the secondary protagonist in the movie Ultraman Tiga, Ultraman Dyna, & Ultraman Gaia: The Decisive Battle in Hyperspace.
One day, a new student named Lisa Nanase moved to Tsutomo's school. With both of them isolated from students (in Tsutomo's case, due to his fanaticsm over Ultraman), Lisa decided to show him something. The next day, after school, she presented him and Yu the Red Sphere, capable of granting wishes. Witnessing his Ultraman Gaia drawing on the floor, this gave him an idea and wished Gamu Takayama to appear in his world. Hiroshi Kashimada, a bully sees this and confiscate the ball from him. He summoned Satanbizor via the ball and the alien rampaged with Tsutomo regaining the ball. Gamu quickly transformed into Ultraman Gaia and finished the alien with ease, despite having his Color Timer blinked in the beginning of the battle. Gamu was later brought to Tsutomo's hideout in order to cover himself from crazed fans. He scanned the Red Sphere before being forcefully teleported back to his dimension. Back in Aerial Base, Gamu studied the scanning he made on the magic ball before teleported into hyperspace where he sees Lisa and behind her a scene of mass destruction. She pleaded Gamu to rescue her universe from destruction.
Meanwhile in the real world, Hiroshi and his friends dreamed of creating a monster that exceeded Satanbizo and defeated Ultraman Gaia as they began to create their ideal monster out of plastic models. Soon, they capture Tsutomo and Yu while regaining the Red Sphere in their possession causing it to turn larger and grow spikes. Hiroshi dragged Tsutomo and Yu to their school's rooftop and summoned his creation, King of Mons into reality. Lisa appeared, having watched the full event. With Gamu as Gaia appeared having difficulty in battling the monster, Tsutomo removed the ball from Hiroshi, causing him and his subordinates to regain their sanity as they felt remorse for their actions. However, it landed on Yu's hands, corrupting him as he shouted his desire to destroy the world, spawning Bajiris and Scylla. As King of Mons' Climate Beam hit the school, the ball moved from Yu's possession, regaining his conciousness. Tsutomo quickly grabbed the ball and summoned Ultraman Tiga and Ultraman Dyna. After the Ultras finished battling the monster, the ball returned back to it's original form. Lisa revealed herself to be an interface of the Red Sphere. She urged Tsutomo to wish the ball to disappear, as he forcibly agreed, causing it to vanish, followed by Lisa, Tiga, Dyna and Gamu but not revealing that he can still meet him due to his book.
The day was later repeated by the Red Sphere but the real Lisa Nanase appeared as a new student. Tsutomo later brought her to the school's rooftop to show her his book, Gulliver's Travels with Gamu's signature. An XIG Fighter EX belonged to Gamu appeared in the sky, passed the two students and vanished. Unfortunately, Lisa missed the opportunity to witness the jet.
- Lisa's actress would later portray Alien Gyashi Shau in Ultraman Cosmos 2: The Blue Planet and Ultraman Cosmos Vs Ultraman Justice: The Final Battle.
- Despite the Red Sphere being corrupted by Hiroshi, Lisa was not affected despite being part of the ball.