Rotom Dex or "Rotom" is a living Pokedex used by Ash in the Alola region. He is voiced by Dyno8Man
Rotom first appeared in the episode "Rocket 'n' Rotom". The Pokedex itself was made by Professor Kukui as a present for Ash. Kukui also used the Pokedex so he can look at pornographic pictures of Ash's Mother on the internet... stating that he needs to clear his history. The professor then allowed a Rotom to go inside the Pokedex to make it work. This allowed it to become Rotom Dex. He scanned the room and identified Rockruff, Pikachu and Ash as "Puppy, Clown Rat Thing and Mental Patient". He then met Kukui, who explained he is an artificial intelligence designed to explore. He became stressed when Ash asked to talk about Digimon (the stress comes from Rotom not being able to find any information). Despite the Pokedex being technically haunted, he still runs on battery. Pikachu decided to help by zapping him. This caused Rotom to remind them to use the recommended charger.
He later met Ash's friends, Mallow, Kiawe, Sophocles, Lana and Lillie who took a liking to him. Mallow assumed he was a Nintendo 2DS. However, he confirmed he couldn't play games but was loaded with over 1,000 Italian food recipes. Sophocles then attempted to "look inside" of Rotom, only to have him hastily decline. He then met Principal Oak and became scared at his possible mental instability. After being told everyone in the class will be unsupervised, Rotom accompanied Ash and his classmates to go have sushi.
Whilst walking through the woods, Rotom and the class came across a wild Mimikyu who has an uncontrollable hatred for Ash's Pikachu. He then met Team Rocket who attempted to battle Ash's Pikachu. They where quickly abducted by a wild Bewear, however. As they were being carried off, Rotom scanned the Bewear, stating that when they aren't working at Chuck-E-Cheese, they tend to kidnap innocent hikers. Once Team Rocket were taken, Ash suggested they all go back to his house for lemonade (which Ash claimed he did not find in the toilet).
Rotom accompanied Ash and Mallow on their date in "Time Flies". When Ash nursed a Rowlet back to health, Rotom noticed that it was nearly impossible for Rowlet to be eating the way it was. When Rowlet stole a Watermelon brought by Mallow, Rotom along with Ash and Mallow proceeded to follow. They then found Rowlet's nest which was home to Toucan Sam, Rowlet's Mom and multiple Pikipek. They decided not to charge Rowlet with "Grand Theft Watermelon" after seeing he needed it more. Suddenly, Team Rocket attacked and attempted to steal the fruit owned by Rowlet's family. However, Team Rocket were one-by-one, kidnapped by Bewear and taken away. Rowlet decided to join the team and flew into Ash's backpack. Rotom took a picture of Rowlet in Ash's Backpack and threatened to email it to every animal rights group in the region if Ash didn't upgrade his programming as promised.
Rotom is very basic in terms of personality. He is informative and observant as his purpose is to analyse everything around him. However, he can become stressed easily, as shown in his first episode as Ash asked him about Digimon and he became stressed and frustrated that he could not find any information. He has proven to be manipulative at times too, threatening to have Ash reported to animal activists in order to have his programming updated. He also appears to have a very negative view of the world based on the first three things it met, stating "this world sucks balls!". He seems to be scared of Sophocles as he wants to "open him up from the inside". As Rotom said "I don't swing that way!", it implies Sophocles is acting in a somewhat sexual nature towards him in his point of view.
- Rotom is voiced by Dyno8Man who also voices Meowth
- In Rotom form, he was voiced by Anthony Fernandez who is the voice of Ash
- His functions appear to be as a Pokedex, necromancy, the internet, Italian recipes and as a camera