"Monster Musume" is a Japanese phrase often found in adult anime and manga genres. It can be translated into English as "Monster Girl". These tags generally refer to content where the female characters are depicted with monstrous or supernatural features, such as horns, tails, scales, fangs, etc. The term also sometimes implies that these characters may possess magical abilities or transformations. This genre is particularly popular in Japan and has a significant following worldwide among fans of adult anime and manga.