A pair of large pink sphere earrings, each inscribed with one of the two kanji "催" and "眠" (hypnosis). In some variations other kanji such as "発情" (in heat) or "洗脳" (brainwashing) are used.
The initial concept was developed by artist Roki in post #2132697 featuring Hata No Kokoro in a dancer costume (the earrings did not yet have kanji on them at this time). It later gained popularity due to the success of a series of related MMD videos created by the artist Furui, who added the kanji element. It has now become kind of a meme attire related to hypnosis.
