Role in the Series-
Doctor Nefarious is one of Queen Vixion's villainous team and he is her love interest until Dr. Nefarious decides to break up with her in Sonja's Adventures of Ratchet and Clank-All 4 One to join Sonja and her friends in their adventures. Sonja and Nefarious used to be enemies at first and now they are friends in Sonja's Adventures of Ratchet and Clank-All 4 One.
Doctor Nefarious was characterized as being extremely evil, eccentric, maniacal and insane. He had absolutely no remorse in his actions and cared only for his personal gain. He showed enjoyment in his diabolical endeavors. His treatment of the Fongoids also showed much cruelty, and his disregard for Courtney Gears' affections showed him to be very cold and uncaring, despite Qwark's insulting her offending him later, suggesting he retained at least some feelings for her but chose not to show them. He showed complete impatience for his servants failing him, shown when he threw a complete fit of rage at Lord Vorselon and entirely double-crossed the Valkyries possibly due to Cassiopeia's disobedience. The Doctor was also well known for being conceited and egomaniacal; his inventions and structures were usually made in his image, his robot servants commonly resembled his features and/or had mannerisms like his, and he tended to pass his ideals onto his subordinates.
However, the final cutscene after the credits of All 4 One implies that his companionship with the heroes may have changed him, as he is shown close to tears while looking at a photograph of him, Ratchet, Clank and Qwark.
Despite the Doctor's extreme hatred for organic life. He was not above working with them to obtain his desires. Nefarious has also shown to be extremely cunning, knowing full well how to manipulate others to get what he wants. This is shown by how he forged an alliance with the Tyhrranoids, the Fongoids, and the Zoni; as well as how he had Lord Vorselon and the Valkyries come to his side with the respective promises of a new body and a home planet. However, that did not stop him from betraying them when either their usefulness had run its course or they disappointed him.
Despite the doctor's self-proclaimed genius (which was undeniable, as masterful engineering must have been required to build weapons as advanced as the Biobliterator or the Hypernova Defense Laser), his common sense at times was questionable by his actions. Two prominent examples of this are his failure to recognize Lawrence's sarcastic responses towards him, and his rehearsal of "Night of the Living Squishies" play with a loaded gun without engaging the safety because he initially believed it was not loaded.
Queen Vixion Edit
Nefarious' ex-love interest. She and Nefarious both get along so well. He tells Vixion joke which it makes her laugh each time when Nefarious tells her a joke. In All 4 One, Nefarious breaks up with Vixion in order to join with Sonja and her friends, betraying Vixion's heart.
Sonja Farrington Edit
Sonja and Nefarious are both enemies at first in the past, until in Sonja's Adventures of Ratchet and Clank-All 4 One, he becomes friends with Sonja and reforms to join with her.
Minami Kaido/Cure Mermaid Edit
Nefarious' new love interest/girlfriend. When he first saw Minami singing. He fell in love with her and finds her beautiful and enchanting. Minami found Nefarious very amusing when he gets angry and plays the space opera Lance and Janice, he also loved seeing Minami swimming in the sea as a mermaid, singing like a beautiful siren, and doing ballet, Minami is also impressed by his intelligence and sense of humour in their adventures. During in their adventures, their relationship grew stronger and healthier, especially when Minami kissed him in the cheek. Sometimes, Nefarious nicknames her "Mermaid Beauty", "Marine Flower", or "Sugar Blossom" which made Minami blush and thinks that Nefarious has a massive crush on her. However, when Nefarious is back of being a robot, Minami doesn't seem to be upset about it, instead she's okay of Nefarious being a robot
Captain Qwark Edit
He gets bullied by Captain Qwark in Ratchet and Clank-Up Your Arsenal and gets defeated by Qwark too. When Qwark is about to give him a wedgie, Nefarious falls off which it causes him to transform into a robot. When Nefarious reformed and joined with Sonja and the others he and Qwark started to become friends a little bit but they can get in fights sometimes.