Misty's first appearance was in the very first episode of the anime series, Pokémon - I Choose You!. In this episode, she first meets Ash after fishing him out of the water when he was trying to get away from Spearow. Ash then takes Misty's bike from her in order to escape the Spearow, which is then wrecked by Pikachu'sThunderShock. Misty then tracks down Ash and follows him around on his adventures until he can pay her back. She eventually forgets about the bike and becomes one of Ash's closest friends. She is also the Cerulean CityGym Leader.
The youngest of the Four Cerulean Sisters. Misty's personality in the anime can be very complex at times. She can be very nice to her friends but will then quickly change moods in a short amount of time, particularly anger. She is quite proficient in anything having to do with water as can be seen in certain episodes where she has ability in fishing, swimming, and overall Water Pokémon training.
Eventually, after the Silver Conference in Johto, Misty's bike was repaired, leaving Misty without an excuse to follow Ash around. Around this time, Misty's sisters call her to inform her that they are going on a world tour and need her back at the Gym. Even though she wanted to stay with Ash, Misty felt obligated to watch over the Gym. The two went their separate ways, and Misty became the official Gym Leader at Cerulean City's Gym.
In the series, Misty first is seen wearing a yellow tank top with red suspenders and light blue denim shorts. Her shoes were colored red and white, with a yellow streak in the middle. In this costume, her midriff was showing, although her belly button is not most of the time (it is, however, shown when she is wearing a bikini).
Misty's second costume is later shown after she meets up with the main group in Hoenn, after she had already left. Here she wears a yellow, sleeveless jacket with a blue collar, and a large blue button. She also wears short, form-fitting shorts that is connected to a crimson colored upper body piece, which may be a swimsuit. Her shoes are now light and burnt orange.
In Pokémon Chronicles, Misty is wearing a sleeveless yellow sweater and a blue shorts and a white belt and dark purple shoes.
Misty has only appeared as a guest star in the remainder of the Pokémon series. In one of her cameo appearances in the Advanced Generation series, her Togepievolves into Togetic. Misty releases Togetic after it chooses to stay behind to defend the Mirage Kingdom. After Ash finishes competing in the Hoenn League, he returns home to Pallet Town to find Misty waiting for him. However, she isn't the only one to rejoin Ash, as May, Max, and Brock join him as well for the Battle Frontier challenges. She travels with Ash for two episodes, and shortly after returns to her Gym.
In Jirachi Wish Maker, Ash mentions that he misses her every day and that they will always be friends forever (English dub only).
Diamond and Pearl series
Misty did not appear at all during the Diamond and Pearl series, although Ash mentioned her to Dawn when he once used her fishing lure to catch Buizel.
Misty is seen briefly in Pokémon DP Special Episode 2 in a photo, as well as May, Max, Ash, Pikachu, Dawn, and Piplup, in memory of their absence from the series.
Black and White series
Misty appeared in a series of flashbacks in BW118 when Ash tells the story of how he raised a Charmander that evolved into a Charizard, but has not had appeared in-person since the special, The Mastermind of Mirage Pokémon.
Misty has a slight inferiority complex, mostly due to her three sisters Daisy, Lily, and Violet who formed the group "The Three Sensational Sisters" (their synchronized swimming group) and refer to Misty as the "runt". This complex diminishes over time as Misty grows closer to Daisy. The Sensational Sisters are the ones who usually run the Cerulean Gym, although Misty battled Ash when he challenged the Gym for his Cascade Badge.
Early in the series, Misty is depicted as having a quick temper, spoiled attitude, and being stubborn, as she and Ash are traveling through Viridian Forest,
Misty's least favorite Pokémon are Bug-types; she freaks out, whenever she encounters a Bug-type, this was first introduced when she refused to befriend Ash's Caterpie. Misty makes a statement that,Bugs are one of the three things she strongly dislikes, the other two being carrots and peppers. The only Bug-type Pokémon that Misty is not scared are ones that she thinks are cute or pretty like, Butterfree and Ledyba, or some that don't look like bugs, like Pineco, also there some she think there great like Heracross.
As the series continues, she gradually shows herself to be kind and sensible. She restrains Brock from girls, often pulling him away by the ear.
When a Pokémonegg that Ash had been carrying in his backpack hatches, the new-born PokémonTogepi chooses Misty as its "Mama". This causes Misty to take on a motherly role to Togepi, being virtually inseparable from it until its evolution. After it evolved, she released it into the Mirage Kingdom to protect other Togepi. She also has undeniable romantic feelings for Ash, which is hinted numerous time throughout the show and some of the songs she sings in (such as Misty's Song, which she sings about her love for him), though she never confesses, and Ash seems oblivious to her feelings.
She is currently the leader for the Cerulean City gym.
Misty's Politoed is one of Misty's Pokémon that she caught in the Orange Islands as a Poliwag. It evolve from Poliwag to Poliwhirl in "The Totodile Duel" and evolved again from Poliwhirl to Politoed in "Outrageous Fortunes" when it accidentally touched a King's Rock, causing it to evolve. It currently resides in the Cerulean Gym with Misty.
Ash found it as an egg and soon it hatched into a Togepi. Ash wanted it, but Togepi liked Misty, so it chose Misty. When Misty visited Ash on his Hoenn journey, Team Rocket invaded and Togepi evolved into Togetic. Misty left it to protect the Togepi Kingdom in the episode of Togepi Mirage.
Misty is the first victim of the recurring gag in the anime where Ash's Pikachu destroys every main female character's bike. This gag was also transferred to May and Dawn. However the gag did not affect Iris because she did not have a bike.
In the anime, Misty possess a fear of most Bug-type (although certain bug Pokémon like Ash's Butterfree and Ash's Heracross don't seem to bother her). Both she and May have fear of Bug-type Pokémon, although May had overcome this fear after her Wurmple fully evolved into a Beautifly. It is unknown how she might react to encountering a Surskit due to it currently being the only known Bug/Water Dual type (however given her specializing in Water Pokémon it is likely she might not be afraid of them as she would other Bug-type Pokémon.
She also has a fear on Gyarados after crawling into its mouth as a baby, despite it is part Water-type. She overcame this fear and she had a Gyarados on her own that knows Flamethrower.
Misty was the one who originated the gag of pulling Brock away from pretty women. She pulled Brock on the ear every time he flirted with a pretty woman. This gag transferred to Max in Hoenn and then Brock's Croagunk in Sinnoh (though Croagunk used Poison Jab instead of pulling Brock's ear).
Misty originally called Ash's Caterpie "ugly" and "disgusting" Ash later attempted to leave Misty only to have her secretly following him. One it evolved to Butterfree she warmed up to it.
Misty has 3 things she has a strong dislike for. They are carrots , peppers, and bugs stated in episode 3 of the first series.
At the end of Misty's journey Brock confirmed that Ash, Misty, and himself were best friends.
In the second Pokemon movie , Misty get jealous after Melody kisses Ash. She denies liking him and being his girlfreind though.