A bracketed face with a wide content laugh. The 〔 and 〕 brackets are CJK “tortoise shell” brackets — heavier and more square than standard parens. They give this kaomoji a slightly formal, almost printed look. Inside, the eyes ´ and ` are angled brow accents, the mouth ∇ is a wide downward open mouth (laughing), and the full-width tilde-equivalent makes everything feel weighted.
The tortoise-shell brackets are the distinctive feature. They are mostly used in Japanese print to set off quoted material or special terms, so when they appear around a kaomoji face the effect is slightly more formal or “official” than standard parens. It is the kaomoji equivalent of a printed smiley rather than a handwritten one.
Use it in contexts where you want a smile that feels deliberate or even slightly retro: announcement messages, signature lines, posts that hark back to early-2000s Japanese internet culture. On Discord it works in anime / Japanese-language servers as a callback. On Twitter/X it suits otaku-leaning bios and replies. Most non-Japanese readers will not register the difference between 〔 〕 and ( ) but it still reads as a smile.
The Japanese match for this style of bracketed kaomoji is おしらせがお (oshirase gao — “announcement face”). Pair with phrases like おしらせです (‘oshirase desu’ — “this is an announcement”) or, more casually, わらい (warai — laughing) at the end of a humorous message.