|“||I'll make shine brilliantly my own color!||„|
|~ Aine before her performance in season 2|
Aine Yūki (友希あいね) is one of the two protagonists of the Aikatsu Friends! series. She is a student of Star Harmony Academy, initially having attended the normal division before transferring to the idol division. Aine is a cute-type idol whose preferred brand is Sugar Melody. Along with Mio Minato, the two are a part of Pure Palette.
Aine has fair skin and vibrant red and orange eyes with flecks of yellow. She has thickly curled cornflower lilac-pink hair with a chardonnay-orange ombre. Her bangs are straight cut and worn with a sky blue headband that has a bow on the corner, while her short curled forelocks are worn over her shoulder beneath the ear.
As of season two, Aine's hair has grown slightly longer and curlier, which she now tied up slightly at the back, with some strands falling over her shoulders on either side. She has replaced the headband with a sky blue bow, which is worn on the right side of her head.
At the age of two, Aine had her small amount of hair tied up with a mini sky blue bow. As she grew older and had more hair, Aine adapted the twin pigtail hairstyle, held by mini bows as well. Reaching the age of eight, Aine let her hair down to shoulder's length, in which had developed great volume, and retained the bows, but this time as hairclips. Her final hairstyle change before her current one was when she reached the age of eleven, in which her side ponytail hairstyle was held up by a ribbon-bow that is the most similar to the one she has on her current headband.
Aine is a positive and cheerful person with a kind heart who is known for her ability to make friends easily.
While working at Penguin Café, Aine met Mio by coincidence and started to get to know each other. Mio then asked Aine to join her on her Aikatsu! activities, but Aine is starting out rough.
- They instantly bonded after Aine made a delivery to drop off the lunch she ordered, and after forgetting to pay for the food she later returned to Penguin Cafe. After playing with Aine and her little brother she came to the decision to ask Aine to team up with her for the upcoming Aikatsu event and Aine accepted, now seeing them as friends.
- Tamaki is Mio, Aine, Maika and Ema's manager.
- Chiharu was originally helping Aine pick her brand but instead Aine loved her dress designs. Aine inspired Chiharu to create Sugar Melody which she later became the muse of. Their relation is similar to Akari/Sena from Aikatsu! series.
- She is part of Friends Unit Love Me Tear with Karen. Mirai helps Aine fit in the world of idols. Aine enjoys her company and has no problem talking casually with her.
- Aine's father.
- Aine's mother.
- Aine's elder sister.
- Aine's elder brother.
- Aine's younger sister.
- Aine's younger brother.
Yūki (友希) - Yū (友) means friend and ki (希) means hope.
|“||Cards are friends! Let's shine together!||„|
|~ Aine before her performance in season 1|
|“||If a friend is in trouble, I will never refuse to help.||„|
|~ Aine Yūki|
|“||Come at me☆||„|
|~ Aine Yūki|
|“||I'll make one million friends!||„|
|~ Aine's catchphrase|
|“||I can't just tag along with Mio. The world of idols isn't that kind. I should've been trying to overtake Mio from the very start! Both Mio and Mirai are supposed to be my rivals!||„|
|~ Aine Yūki|
|“||To me, you're my one and only as well. Even if I had a million friends, I'd still choose you!||„|
|~ Aine to Mio|
|“||My dream is to make a million friends. Cards are friends, and fans are friends. But even with all my Friendsta followers, I'm still far short of that million, so I thought I was nowhere close to achieving my dream. But it's not the number that matters. Each and every friend...||„|
|~ Aine to Mio|
|“||Every one of them is my precious friend. Each person friends' power pushes me a little further forward. With that in mind, I can feel myself brimming with more power than ever.||„|
|~ Aine to Mio|
- She is 155cm tall.
- She is tied with Mio as the shortest main characters.
- Her star sign is Cancer.
- She loves her family.
- She likes animals, her favorite being the penguin.
- She dislikes crying.
- Her favorite food is the tomato basil and cheese sandwich.
- Her specialties are music, getting along with others, and small talk.
- She shares her birthday with Minami Kaido from Go! Princess Pretty Cure.
- Like the other main protagonists in the Aikatsu! franchise she has a trademark bow in her hair, is a Cute-type Idol, and has a pink theme color.
- Like Ichigo and Yume, she also performed a Special Appeal and obtained an Idol Aura in her very first stage performance.
- Coincidentally, she shares her eye color with Yume Nijino.
- Aine is the third protagonist whose family runs a food store.
- Aine is the first main protagonist to already be a second-year middle school student in her introduction.
- She is also the first main protagonist whose trademark bow isn't a shade of pink or red.
- She is the first protagonist whose debut performance is not a solo, but a duet.
- She is the only protagonist who has never had flowers in her aura.
- Like Ichigo, her primary brand has the word 'Sugar' in it.
- She is the first protagonist whose surname doesn't have anything to do with a phenomenon in the sky.
- Aine is the third main character in the Aikatsu! franchise to change her hairstyle, following Akari Ōzora from the original Aikatsu! series and Yume Nijino from the Aikatsu Stars! series.
- Aine is the sixth character in the Aikatsu! franchise to have ombre hair, following Sora Kazesawa, Nina Dōjima from the original Aikatsu! series, as well as Yume Nijino, Yozora Kasumi, Lilie Shirogane from the Aikatsu Stars! series.
- She is the eleventh character overall in the Aikatsu! franchise to have dual colored hair, following Sora Kazesawa, Mikuru Natsuki, Rin Kurosawa, Nina Dōjima from the original Aikatsu! series, Yume Nijino, Tsubasa Kisaragi, Yozora Kasumi, Lilie Shirogane, Elza Forte and Kirara Hanazono from the Aikatsu Stars! series.
- She is the seventh character overall in the Aikatsu! franchise to have dual colored eyes, following Mikuru Natsuki, Nono Daichi and Nina Dōjima from the original Aikatsu! series, as well as Yume Nijino, Mahiru Kasumi and Lilie Shirogane from the Aikatsu Stars! series.
- Aine bears resemblance to Orine Aida from the AKB0048 series.
- They both have ombre pink hair.