Noodlekin (also known as noodle kin, Noodle, and Millie) is an American Project Arrhythmia level creator and one of two co-creators of the Heartstrings storyline, being the sole creator of its levels. They originally joined in December 2019 but then left until returning in March 2020. Noodlekin is also a visual artist, and has drawn several level thumbnails as well as artwork of their characters. Most of noodlekin's levels are Expert or Advanced difficulty.
- Twilight - released March 20, 2020
- Red Haze - released March 25, 2020
- Spectra - released April 8, 2020
- Euphoria - released June 5, 2020
- Stardust - released August 10, 2020
- Ordinary - released November 5, 2020
- Hate - released March 11, 2021
- Aurora - released April 16, 2021
- Goldfinch - released July 30, 2022
- bibibibibi - released July 17, 2020. A joke level featuring Spectra.
- geer pint - released April 11, 2020
- Pixels - released October 2, 2020
- Turn Around (VIP) - released January 28, 2021
- Close to Me - a collaboration with DXL44 to remake the Just Shapes and Beats level of the same name
- World is Mine - Another fan-level featuring Lumi in a new form.
- Noodlekin's profile picture features their character Deco, who is featured in an unfinished level.