noun
womb tattoo; inmon
A stylized uterus-shaped mark below a female's navel, usually appearing in pornographic or erotic contexts. The term is colloquial and primarily used within otaku and adult-content circles.
その同人誌のヒロインには淫紋が描かれていた。
The heroine in that doujinshi had a womb tattoo drawn on her.
淫紋は成人向け作品でよく見られる記号だ。
The inmon is a symbol often seen in adult-oriented works.