|Also Known As||Hotaru Saijou|
|First Appearance||Season 2|
Rapunzel Saijou (西條 ラプンツェル, Saijō Rapunzeru, born Hotaru Saijou), commonly known as Zel, is a Japanese girl who is taken in by Primavera after her involvement in a car accident. She serves as the protagonist of Season 2 of Rose Guns Days.
Zel was born in Japanese-occupied China wherein her father was promoting the Greater East Asia Co-Prosperity Sphere. Her father was arrested after the Japanese surrender and Zel was sold into slavery.
Zel appears as a young girl with long light brown hair adorned with a teal accessory. She typically wears an orange and teal dress with detached sleeves and golden embroidery alongside a bolo tie. Her long hair is what inspired Rose Haibara to give her the name "Rapunzel."
Zel is given orders from the Golden Dragons to throw herself in front of Rose Haibara's car in order to infiltrate Primavera and eventually assassinate Rose. However, the car accident gives Zel genuine amnesia, causing her to forget her true identity for around two months. During this time, she befriends Oliver Oribe, Charles Chatani, and Nina Ninagi. Upon remembering her original mission, she nearly assassinates Rose but stops herself. This leads to her identity being revealed. Her life is spared per Roses's orders, however she is excommunicated from Primavera.
After the death of Yuanhong Wang, Zel and her father leave the country, though Zel promises her friends that she will eventually return.
In 1950, Zel returns to Japan and reunites with Charles Chatani and Nina Ninagi, regaling them about her time working on a coffee farm. She tells them that the reason for her return is due to discrepancies in the letters Zel had been exchanging with Rose Haibara; ever since Rose was shot a year prior, her letters have been strangely written. Zel, Charles, and Nina deduce the truth of Rose's imprisonment and team up with Leo Shishigami and Jeanne Amakawa to rescue her.
- Zel wears a bolo tie, a piece of clothing typically associated with the "Wild West" era of the United States. In the real world, bolo ties were not popular in East Asia until the 1980s, however it is possible the alternate history depicted in Rose Guns Days led to their early popularization due to the greater influence of American culture.