Rozalin is the daughter of Overlord Zenon, although she has lived most of her life sequestered in a massive mansion surrounded by servants and given everything she could have ever wanted. One such servant is Tink, who later gets turned into a frog. Mom attempts to summon Overlord Zenon, but instead summons her and ends up binding her to Adell. Being stuck with Adell, she attempts to rid herself of him by secretly planning to kill him. Her attempts however always end in failure due to Adell overcoming the trap or the trap turning on Rozalin, forcing Adell to save her. Due to being locked up inside her mansion, Rozalin not only doesn't know how to fight properly but she also doesn't know where her mansion was actually located. She is also inexperienced in the ways of the outside world, relying only on what she learned in text books from her Mansion's library. She also often announces to people that she is "Overlord Zenon's One and Only Daughter" while flashing the Four Leaf Clover mark she has, claiming it to be a symbol of the bond she has with her father. After the battle with Demon Lord Etna it is revealed that Rozalin doesn't even know where Overlord Zenon is nor what he even looks like. Over the course of the story, Rozalin grows more as a person and learns to like Taro, Hanako and even Adell. During the Tournament Arc, it is shown that she is unsure of what to do if the group wins the tournament and is granted the chance to see Zenon due to her experiences in the outside world. It also revealed that she is in fact a closet Prism Rangers fan. When the group goes to Shinra Tower to get herbs to help Fubuki (with Etna wanting to find something to fix her loss of levels), they come across Laharl who not only annihilates them in a fight but also smashes Rozalin's Four Leaf Clover mark which is soon revealed to be a seal holding back the soul of the true Zenon. Laharl, surprised by Rozalin's increase in power, is defeated so he decides to take his leave and come back for Etna later. Rozalin is unable to control Zenon's soul until Adell snaps her out of it (by slapping her). During the Final Battle with the False Zenon, the real Zenon tells Rozalin to shatter the seal again if she wishes to help her friends. She does so and the real Zenon destroys the impostor with a single blast. In the good ending Rozalin soon aims her wrath at her friends only for Adell to snap her out if it with a kiss (causing her to go ballistic and chase him as shown in the credits). In the worst ending, Adell fights and kills her, only for the soul of the real Zenon to posses him.
Rozalin is the proud daughter of the most powerful demon in the world. Before she met Adell, Overlord Zenon had sequestered her into a sheltered life with no contact with the outside world. She is unlike any human or demon. At first, she views everyone as below her, and considers them all her slaves and servants, but as time passes she begins to have more respect for her allies. As the plot in Disgaea 2 moves on, she begins to question what her father really thinks of her and why he hasn't come to rescue her.
She first met with Falica and Dimitri. She Teamed up with them and joined forces with The Court of Demons Council. She offered Myotismon her heart to open the final Door of darkness, where Konohamaru's father and Garnet's husband have imprisoned before the child's birth. Dimitri watched tails and cosmo frightend by Konohamru's father. She had determined the TheCourt of Demons Council wolud fail if she did not reveal her truth.
- Since she really was Overlord Zenon but has reincarnated, then the summoning Adell's mom made really did work and really did summon Zenon.
- The gun she shown in her concept art and in the Disgaea 2: Dark Hero Days Intro is named "Noble Rose".