Felix was originally obsessed with cleanliness to the point that he considered even people germs that must be "sterilized" at all costs. It is also shown that Felix has a defect that kicks in when he's faced with anything aged or antique because he doesn't understand the concept of antiques, and as far as he knows, they only collect dust.
After Felix was reprogrammed, he became obsessed with dirt. The only thing that Felix can say with both of his upgrades is "Dirty!", but with Felix he says it disgustedly, while with Oscar he says it happily.
Felix is currently obsessed with cleanliness instead of dirt.
Experiment 010 was the 10th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to keep Jumba's house clean and tidy, but due to a glitch in his program, he viewed all organisms (including people) as germs that must be "sterilized" at all costs, and threw away anything even remotely dirty. 010 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
All of the experiment pods were released and scattered across the island of Kauai.
At an unknown point after this, Experiment 010 was activated and captured by Gantu.
Due to 010's tendency to throw out anything that was even remotely filthy (including prized belongings), Gantu sent 010 to Hämsterviel, but he also found 010 annoying, and thus sent him back to Gantu, who abandoned 010.
Felix's cleanliness proved useful at home, which fascinated Pleakley to the point that he befriended Felix, until he began destroying and throwing out Lilo, Stitch, Jumba and Pleakley's personal belongings.
Eventually, Felix decided to "sterilize" the residents as well, and, locking them inside the house (save Pleakley, who was locked outside), relentlessly pursued them until they were able to trap him in a container.
Jumba then reprogrammed Felix to be less of a neat freak, but instead of just liking dirt, it caused Felix to begin making things incredibly dirty.
Lilo and Stitch later sent Felix back to Gantu as a present, but due to the experiment's new programming, rather than help Gantu clean up his ship like the latter hoped, Felix made it even dirtier.
It can be presumed that Felix was sent back to Hämsterviel after this messy incident.
In "Remmy", Felix was one of the experiments in Lilo's dream.
Felix reappeared in "Snafu", and was freed along with Gantu's other captive experiments by Lilo, Stitch, and several other experiments in a rescue mission.
Felix was one of the experiments that was gliding on the screen, but he is 602 instead of 010.
The first 624 experiments, including Felix, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben and Gantu arrived before the experiments could be destroyed.
It is unknown whether or not Felix participated in the following battle between the experiments and the Leroy clones.
The Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song "Aloha ʻOe", which caused the Leroy army to shut down due to the original Leroy's fail-safe.
Felix appeared in his own episode in the Stitch! anime where Stitch summoned him so he could get out of cleaning the house. In this episode, it is shown that Felix has a defect that kicks in when he is faced with anything antique. However, Felix doesn't understand the concept of antiques, and as far as he knows, they only collect dust. Thus, his programming causes him to terminate anything aged in order to prevent the buildup of dust. In the end, he is reprogrammed to collect things that can be renewed and recycles them. His one true place after this is as a mobile recycling service. Felix makes another appearance in the Season 1 finale "Showdown with Hämsterviel" where Hämsterviel puts him along with Sparky and Angel under his control.Tokyo Disneyland, Felix is a popular character, being that his franchise is extremely popular in Japan. Other than Tokyo, Felix is not seen in any other park around the world.
In Tokyo Disneyland, Felix joins other Disney characters as they celebrate the magic inside everyone's hearts.
- Both of 010's names are a reference to the main characters of The Odd Couple.
- Felix appears, along with several other Lilo & Stitch characters, in a parody of the Disney Channel Original Movie High School Musical, which was broadcast as part of the High School Musical: Around the World one-year anniversary special.
- Felix's pod color is green.
- Felix is described by the experiment computer screen as, "Experiment 010. Primary function: Cleaner."
- Felix's antennae appear in the online game Jumba's Lab.
- Felix's design resembles some monsters from the Ultraman series, such as Sartan (The Return of Ultraman), Zurzula (Ultraman 80), and Gazebo (Ultraman: Towards the Future), mainly because of their long noses and elephant-like appearance.