Aguri Madoka (or Natalie Miller in the English dub) is one of the Cures in Doki Doki! Pretty Cure. She is a mysterious character who appears. in the end of Episode 22, while saving the Cures' life. She finally reveals herself as Aguri in Episode 23. She is very wise for her age, and has a major sweet tooth. Aguri's alter ago is Cure Ace. She uses Dina's power to transform. It was revealed in Episode 45 that she is the light of Princess Marie Ange and Regina is her darkness, revealing she is Princess of Trump Kingdom.
Aguri has long brown hair with a small ponytail tied at the back of her head and maroon eyes. She really looks like Regina when her fringe is down. Her summer clothes are composed of a red short-sleeved dress with a white collar and white stripes at the bottom of the skirt. She also wears red shoes with white socks. Her warmer clothes are composed of a long-sleeved red jacket with a black and white collar and a red undershirt. She also wears a black layered skirt and reddish-brown boots.
As Glitter Ace, she ages physically to a 17 years old. Ace wears a white and red short-sleeved overcoat with pink accents with a short red dress underneath it. She wears a thin gold choker around her neck and knee-length white and red boots. There is a gold heart-shaped brooch with pink ribbons at the bottom. Her wristbands look similar to Glitter Clover's. Her hair becomes long and red and gathered into a ponytail and also with a gold headband with a gold and white bow on the left side.
Natalie is calm and wise beyond her young years. She tends to tell rules to people, and is also strict, reaching the point where her comments can be hurtful. She has an appreciation for good food, as seen with the flavor of a peach roll, which she described in great detail, and how she was a regular of a restaurant even since being "drawn" by their anmitsu. She sometimes says "Bravo," mostly when she eats something she thinks tastes good. She would also say "Adieu" when departing.
- Ace Shot - Her main attack, she uses to purify Jikochuus. She needs the Love Kiss Rouge to perform this attack. She needs the Love Kiss Rouge to perform this attack. Depending on the color of lipstick she puts on, the effects of the attack are different.
- Red - used to purify Jikochuus
- Purple - used to freeze enemies in place
- Yellow - used to trap enemies with vines
- Blue - used to encase enemies in a bubble
- Ace Mirror Flash is Glitter Ace secondary individual attack performed with Magical Lovely Pad. It hasn't appeared yet, but it seems that is going to appear in episode 31 or 32 along with the other cures new attacks.
- She is the only Glitter Force Warrior to be represented not by a card suit, but by a card itself, the Ace.
- She is the second Glitter Force Warrior to represent love.
- She is the only Glitter Force Warrior that does not have her fairy in a part of her dress.
- She is the first Pretty Cure to wear make-up in her Cure form.
- Although late-arrival Cures are not uncommon, Glitter Ace is the first late-arrival Cure whose civilian identity was not a character that already appeared.
- Natalie is the second youngest Pretty Cure in civilian form.
- She is the fourth Pretty Cure to have her transformation completely different from her teammates.
- Natalie is the second Pretty Cure to be voiced by one of the Dark Pretty Cure 5's voice actresses (Rie Kugimiya, who voiced Dark Lemonade), following Chloe.
- She is the third Pretty Cure to have a fire-themed transformation, despite her powers not actually being fire-elemental. This also makes her the second Cure to have an element of nature featured in her transformation but not actually having said element as part of her powers.
- She is the second Pretty Cure to be in elementary school.
- Natalie's Cure form, Glitter Ace, looks similar to Princess Marie Ange, and they both share the same initials, M.A or A.M. Later revealed to be because Natalie is the princess' light side.
- She also share the same initials with Maya Aida.
- Glitter Ace's motto, "Beauty is the proof of justice!", is similar to Bad End Beauty's motto, "Beauty is justice."
- Glitter Ace is the first Pretty Cure to have a limited time to be in her Cure form (five minutes).
- She is the second Pretty Cure to have been a Cure before her teammates, lose her ability to transform, and regain her ability to transform again.
- She is the first and currently only Pretty Cure to have an age change during transformation.
- She is the second Pretty Cure and third heroine in general to have the letter "A" as her symbol.
- She is the second Pretty Cure to have her voice change while transformed.
- She is the second red Pretty Cure to have brown hair when not transformed.
- Natalie is the second Pretty Cure whose last name was previously used as a first name for another character.
- She is the second Pretty Cure who does not like carrots although Natalie's dislike was fixed.
- She is the first Pretty Cure who does not know her birthday and star sign as shown in episode 42.
- It was hinted few times that she is maybe somehow related to Princess Marie Ange. It was revealed, that she is the light side of Ange, while Regina is her dark side.
- With her hair down, she looks similar to Regina, later revealed to be because they are counterparts, representing Princess Marie Ange's light and darkness, respectively.
- Many people thought Glitter Ace was Regina mainly because they had the same theme color.
- Due to her identity as Princess Marie Ange's light half, this would mean Aguri is technically a princess. She is the second Pretty Cure to be a princess, preceded by Cure Muse.
- Her face and hairstyle are similar to Kanade Minamino.
- Glitter Ace is the fourth official Pretty Cure in the whole franchise who was already a Cure before appearing in the series in her Cure form; the first three being Cure Moonlight, Cure Muse and Glitter Spade.
- In her Glitter Ace form, she also looks similar to Aphrodite.
- Natalie will appear as Glitter Ace to give the 10th Anniversary Congratulatory Message at the beginning of episode 19 of Happiness Charge Pretty Cure!