As the Strawhats are color coded this comes in, Nami often wears pinks and reds and Robin wears purples while Luffy has blue shorts, Sanji wears blue and Franky has blue hair. Tashigi wears pink which contrasts to Smoker blue and Zoro green. Their disguises often follow the same pattern, with James dressing at the blue end of the spectrum and Jessie at the red, though sometimes as seen in "The Misty Mermaid" they'll switch ends.
Misty is red haired and wears red suspenders while Ash wears a blue jacket and pants. Continued with May red Dawn pink and Serena red and pink. While Lillie usually wears all white though her backpack is pink , her Ultra Guardian uniform is pink while Ash's is blue, continuing the trend. Cheery, perky Sailor Moon has pink, silver, white, or yellow hair in the original manga. Her predestined lover Tuxedo Mask has, depending on the image, dark black, blue, green, or purple hair.
When he is married to Sailor Moon, he has pastel purple hair, which appears to be a symbol of his healing due to being with her. As far as costuming is concerned, though, Sailor Moon herself wears white and blue while Tuxedo Mask wears black and red.
The s anime's Transformation Sequences for the Sailor Starlights involved the background and their bodies changing from blue to pink as they changed from their male disguises to their true female forms.
Amu is a Pink Heroine with a very pink costume and hair color. On the other hand, Ikuto wears blue and has blue hair. Nagihiko's Guardian Characters, the very pink and sort of girlish Temari and the very blue and boyish Rhythm.
Also, Seiyo Academy's school uniforms follow the pattern as well, with the girl uniforms being red and the boy uniforms being blue. Toyed with in the Slayers franchise in regards to the two model couples: For Zelgadis and Amelia , the latter is a princess who has both a pink dress for diplomatic duties and a modest traveling outfit with some pink touches, while the former is a chimera who literally has blue or blue-green colored skin.
In both the anime and The Movie , Speed Racer typically wears blue and white, while his girlfriend Trixie dons pink and red. However, on formal occasions in the anime, Trixie would wear a blue dress while Speed wore a red blazer. Interestingly all three of those series had the same character designer Akiko Shimomoto. They wear a lot of blue and pink respectively in their battle armor, and each have a spider partner in these colors.
A BL example are the title characters of Sukisho - with the uke having pink hair and eyes, while the seme has blue. Not only do Ichigo and Masaya have pink and blue hair, respectively only in the manga, though; the anime changes them to red and black , but their last names are Momomiya and Aoyama!
Even more ironic, the whole Tokyo Mew Mew team is female and all the aliens are male. In the final battle, where Ichigo blasts her final attack, and Deep Blue releases the Mu Aqua, you can clearly see a clash of pink and blue. The Mu children in Toward the Terra have pink dresses for girls and blue jumpsuits for boys. The adults all wear purple. If you look at colored manga pages, or often the anime uses this motif, for Wandering Son you'll notice it's not uncommon for male characters to wear blue and females pink.
Considering the series is themed around gender, it makes sense. The school uniforms in Yu-Gi-Oh! Yugo and Rin have this dynamic when wearing their street clothes. Yugo has a blue t-shirt while Rin has a pink top. Boy pegs are blue, girl pegs are pink. Interestingly, the rules say you have to put a second peg in your car when you get married, but they don't say what color the peg has to be.
Batman's cape and cowl in 80s to 90s was always colored blue until he changes to black while Catwoman wears her purple catsuit. Dick Grayson nearly always wears blue and his love interests: Batgirl, Starfire and Supergirl all have worn either pink, red or purple at some point. While Spiderman has both red and blue in his costume, while living as Peter Parker, Spidey often just wears blue which of course goes with scarlet-haired and dressed Mary Jane Watson. The mutant twins Quicksilver and Scarlet Witch often wear blue and red costumes respectively, although Quicksilver's first costume was green.
Their powers are also color coded, with Scarlet Witch having the red aura and Quicksilver the blue aura. The stars of Sunnyville Stories display this trope in color artwork; Rusty wears blue or red while Samantha wears pink.
Cleo is associated with pink and purple, as are her weapons. Anthony wears blue, and his weapons are have blue energy. The Pink Panther is a girl. If he was a boy he'd be the Blue Panther. In colored printings of Sherman's Lagoon , Sherman a male great white shark is gray — slightly bluish, depending on the inks used — and his wife, Megan, is purplish-gray. Played straight with Mikuru and Kyon; Mikuru's theme color is pink, and while Kyon's theme color is a dull brown it even shows in his Cure costume , his aura as a Cure is blue.
Played straight in Futari Wa Pretty Cure Dimensions by the very tomboyish Megumi Yamada and the somewhat effeminate Ken Ichida, who also happens to be the blue boy to another tomboy who likes pink—his own sister, Chiyoko.
In Rhythmic Pretty Cure , at the karate school Hitomi and Tsumugi go to on Mondays and Thursdays, the boys' karategi is blue, and the girls' karategi is pink. In Harry Potter , Tonks usually went around with spiky pink hair. We don't see much of her son, Teddy in the books, but Fanon has largely agreed that his hair should be blue. Defied in Power Rangers: It's quite explicit as The Mentor personally gave them their colors.