'Sus' is short for suspicious and became internet shorthand through Among Us, the social deduction game released by Innersloth in 2018 that exploded on Twitch and TikTok in 2020. Players spammed 'sus' in chat to vote out possible impostors, and the word escaped into everyday meme slang for anything shady. Elongated readings like 'suuuuus' turned the accusation into a joke in itself, spreading through meme compilations and reaction edits the way sounds like the bruh meme and the oh my god meme did. It survives because the accusation fits almost any suspicious moment.