OneyNG and psychicpebbles/psychoticpebbles (Hellbenders and Smiling Friends)
The Owl House
Panty and Stocking with Garterbelt
Pathfinder
penguinz0/HugeCharles/(Moist)cr1tikal
Phineas and Ferb
Pibby
The Powerpuff Girls
Power Rangers
Predator Poachers
preschool shows
Psycho Goreman
Ranma
Re:Zero
Red Letter Media
Rick and Morty
The Rocky Horror Picture Show
The Room
Rurohni Kenshin
Sailor Moon original series (especially dubbed)
Salad Fingers
Samurai Jack
"scary" logos
Schoolhouse Rock
Scott the Woz
Serial Experiments Lain
SomeOrdinaryGamers
Sony Pictures Animation
South Park (yes, really)
Spindlehorse/Vivziepop
Sr Pelo (AKA Pelo the Pedo)
Steven Universe
Superjail
SuperMarioLogan/SML
both Teen Titans shows
TerminalMontage
TikTok
Tim Rogers
Tomorrow's Joe/Megalobox
Too Loud
Twitch
VShojo
Wakfu
Watamote
We Bear/Baby Bears
Music
Anamanaguchi
Bit Shifter
Boards of Canada
Burzum
Crush 40
Danny Baranowsky/dB Soundworks
The Doors
Drake
GaMetal
GiIvaSunner/SiIvaGunner
Jimmy Screamerclaus
Kanye West
Ken Ashcorp
Kesha
LMFAO
Macintosh Plus
Man on the Internet
mumble and Soundcloud rap
My Chemical Romance
New Kids on the Block
Ninja Sex Party
Panchiko
Post Malone
Ridiculon
Sewerslvt
Sia
Sleep Token
Stemage
Taylor Swift
"trap"
Vocaloid, especially Hatsune Miku
Your Favorite Martian
Reading Material
Anime News Network
Big Nate
Bluesky
Common Sense Media
Cutey Honey
The Daily Wire
Diary of a Wimpy Kid
EFF
Encyclopedia Dramatica
F-List
fallenchungus/datsmojo
FANDOM blogs
Garfield
imageboards
Industrial Society and Its Future
Johnny the Homicidal Maniac
Kotaku
Meta Threads
Natural News (AKA ramblingconspiracybullshit.com, thanks to A Dose of Buckley)
Neocities
Neoseeker
Polygon
The Porn Dude and its subsites
Puyo Nexus
Snafu Comics
Sonichu
StoneToss
"Truth" Social
TV Tropes
Twitter/X
Wikipedia
Multimedia
analog and mascot horror
annoying memes
anything controlled by Retroware/Screenwave Media
Berserk
Buffy the Vampire Slayer
creepy/gross porn
Cuphead
Cyanide and Happiness
Danganronpa sequels
Doraemon
Dorkly
Hello Kitty
hololive
Homestuck/Hiveswap
Hot Wheels
IGN
InfoWars
Invader Zim
Italian Brainrot
Lego
Magica franchise
Miss Kobayashi's Dragon Maid
My Little Pony (yes, really)
Neptunia
Nicktoons
One Piece
Perman
Pop Team Epic/Poputepipikku
Rosario + Vampire
Scott Pilgrim
Sonic franchise
Steins;Gate
Touhou Project (moreso on the Western Hemisphere, ironically)
Transformers
Urusei Yatsura
Yu-Gi-Oh
Diet
advanced.gg
Arby's
Bud Light
Burger King
Cheetos
Chex Mix
chicken tenders
Chick-fil-A
Coca-Cola
Coors Light
Corona
Domino's
Doritos
Factor/Hello Fresh
fruit snacks
Gamer Supps
G-FUEL
Goof Juice
gummy bears
hot dogs
Hot Pockets
Jack Daniel's
KFC
Lays
McDonald's
Monster Energy
Mountain Dew
Papa John's
popcorn
Popeye's
PRIME
Sheetz
Sonic
Soylent
Starbucks
Taco Bell
Takis
tube pops
Wendy's
Stores
DoorDash
Fangamer
GameStop
Humble Bundle
kikagoods
Maestro Media
Makeship
Nicalis
one dollar/pound shops
Ownaj
Sharkrobot
Steam
Target
Uber Eats
uwumarket
Walmart
Youtooz
Hardware
Amazon anything
Apple anything
Divoom
Raspberry Pi
Samsung Galaxy
teledildonics
Software
Adobe anything
Apache
Arch Linux
Asahi Linux
Brave Browser
Cash App
ChatGPT
Discord
Docker
Emacs
fantasy computers and consoles
Firefox
GitHub
Godot
Google Drive and Maps
Infinite Craft
Kali Linux
LARBS
Mastodon
Microsoft Azure/OneDrive
node.js
Opera GX
password manager
PayPal
Plex
RPG Maker
Slack
Telegram
TempleOS
Unity
VirtualBox
WordPress
XSplit
Zoom
Conventions
Anime Expo
Awesome Con
Comic Con
Creator Clash
Fan Expo
GDC
Gencon
Gen Pop
MAGFest
MLP Cons
Momocon
PAX
Portland Retro Gaming Expo
Sonic Expo
Sonic Revolution
Twitchcon
UK Gaming Expo
VidCon
Youmacon
Other
autism/"neurodivergence"
baseball/dad/snapback hats
beanie hats
bean smiles
black dot pupils/"Michael Myers eyes"
blank stares
BPD
completionism
dead babies
disrespectful behavior
dog collars/"chokers"
domain name squatting
Funko
Indiegogo
Kickstarter
ko-fi
nitrous oxide/Galaxy Gas
NPD
obesity
OnlyFans
Patreon
plaid clothes
podcasts
reckless driving
red shirts
road trips
sexual ASMR
skulls without jaws
steam trains
subscription boxes
Keep in mind that one is not a kidult just because they like children-aimed media; Walt Disney even stated "Adults are kids grown-up, after all." Kidulthood usually combines specific interests with immature actions.