The "Act Yandere Without Saying a Word" Game is a Manga/Manhwa/Manhua in (English/Raw) language, COMEDY
series, english chapters have been translated and you can read them here. You are reading chapters on www.mcreader.net fastest updating comic site. The Summary is
A bunch of girls try their best to give off a "yandere" vibe silently while their classmates rate their performance.