Honkai Impact 3 is a mobile game with elements of role-playing and gacha games. It features an anime-style aesthetic and focuses on battles against a mythical force called the "Honkai." The game has adult content in some of its character designs and storylines, which could be included in porn videos as tags. The tag "honkai-impact-3rd" refers to the use of characters, settings, or scenarios from this game within adult content. It implies that a video contains explicit material involving characters and themes from Honkai Impact 3.