Natsuki had black spiky hair tied back into a long braid. She had only one Cross-Eyes on her right eye (later in the story she gets two Cross-Eyes but for the most part has only one).
Easy going with a happy nature, always looking at the bright side and hoping to help anyone who she thinks its her senior (when she looked at Kaiman's Cross-Eyes, immediately considered him an organization member above her, in other words, her senpai).
Eager to tease people kissing them and jokingly (and some times seriously) expressing feelings for them, when Nikaido, Kaiman and her were at the luxury hostel in Berith, she got drunk and kissed Kaiman telling she loved him, later she would feel disappointed for be unable to kiss Dokuga because his poison spit, and tell everybody about how much she respect and loves The Boss, wishing to become his woman one day.
Introduced when Nikaido and Kaiman escaped from En's Mansion thanks to Asu, they were teleported to the city of Mastema, and almost abandoned place were En fought The Boss six years ago, Natsuki mistook Kaiman for a Cross-Eyes member and help them to get clothes and food. She was approached by Black Powder addict Magic Users who wanted some of it, she shoos them away because they had no money to pay.
Maki, her former superior used to mistreat and hit her regularly, she never tried to reply at any of it because she believes in the Cross-Eyes and wished to meet The Boss one day. When she found out that the "Black Powder" they were selling was fake, Maki tried to kill her when she said that Black Powder was made to give hope to those unable to produce magic and help to rebuild the organization, she killed him in retaliation using one of her hooks to torn apart his waist.
She tagged along with Nikaido and Kaiman traveling from town to town, helping them in any way she could (mostly paying for their food), when Kaiman had a mental breakdown in the old building of the Zagan Training School, she cured his self inflicted injuries and headed to a luxury hostel in the city of Berith, where she believed the Cross-Eyes would pay for their expenses once the group reaches the organization headquarters, not knowing that the top officers were working in there as part-timers due their lame economic situation.
During the fight between Kaiman and En the hostel was destroyed and she chose to stay with the Cross-Eyes in their hideout, taking small part-time jobs to help them in order to pay for some healing smoke to cure Ton and Tetsujo (both injured after Risu merged with Curse) working as a waitress, Dokuga took her clothes to sneak into Shaitan's smoke shop as a girl and slaughter everyone in there to get the healing smoke they needed.
The Top Officers and her heard the news about En's murder at the hands of The Boss, knowing he has return, they all went to his old apartment to meet him, but they were assaulted by Shin and Noi, who were following a doll to find En's Devil Tumor, Natsuki was able to get into the apartment thanks to Ushishimada, at the cost of all the other officers sacrifice. She found Kai, lying in a bed unconscious after practice a cranial surgery on himself (to put En's Devil Tumor inside his head) horrified, Natsuki used some of the healing smoke that Dokuga got to restore his head and awake him, using a combination of En's Magic and the Holes rain effect on the cleaners, Kai saved the officers, Natsuki healed them and started to rebuild the organization once again.
During the raid in the En's Mansion (now the new Cross-Eyes headquarters) she found a hidden vault filled with gold bars, eager to show it to the Officers to remark how rich they are now, Dokuga and the others were unimpressed, much to her disappointment, in that same moment Ton yelled at them to come quickly to a storage room filled with groceries and toilet paper, the Officers were amazed for all the goods in there and even Dokuga said "So this is what it feels like be rich", Natsuki took this as a weird exaggeration.
Ton and Natsuki were entrusted with the mission to find Kikurage because it was one of the En Family members that the Cross-Eyes didn't found yet, they engage in battle against Fujita and Ebisu, looking for Kikurage too, Ebisu transformed herself into a demonic reptile creature and sliced Natsuki's arm off, this activates the smoke vessels inside her arm, activate her defensive type of magic for the first time, creating a jelly-like coat around her, rendering her invulnerable to any kind of attack, Ton took her and escaped from them. Back in the Mansion, Natsuki fixed her arms and got her left eye tattooed too, the other officers questioned her why she is still with them, with her type of magic she could live a normal life, but replied that she is a Cross-Eye and she would never left them.
Dokuga, knowing the Boss would kill her for her magic, entrusted Natsuki with a "special mission" to send her far away while he tried to reason with him, but before he could do it, thanks to Aikawa's eavesdropping in the conversation between Dokuga and Tetsujo, Kai, as an evil side of Aikawa listened all too and took control of their body, he approached her, knowing how naive she was, he easily killed her, chopping her lib by limb and transforming her corpse into mushrooms, hiding it inside of a statue of Chidaruma in one of the halls of the mansion.
Aikawa, now in control of his body once again, found Kai's laboratory and Natsuki's head in a jar, filled with cables and with a hole in her skull where her Devil Tumor once was, saddened by this, Aikawa took a piece of fabric and covered the jar, giving her a little of dignity in her death.
Ton found her naked inside a puddle of refuse, he took her and tried to escape from the weird place they where, not understanding why he or her didn't remember anything or why that place was endless, Ton remembered his last moments, now fully understanding their situation, he apologized to Natsuki for not be able to protect her, realizing they were nothing more than Devil Tumors inside Artificial Devil Kai.
- Wants to become useful for the boss
- Wants to be more like an adult
- Wants to be on better terms with the cross eye officers
- Has jealousy towards the elite magic users
- Hopes for the future