[Onee-san to Issho] Josou Idol wa Futsuu no Otokonoko

Anal intercourse is a common sexual act tag in doujinshi. It appears across nearly all genres and demographics, from vanilla romance to extreme fetish content. The artistic depiction ranges from realistic anatomy to highly stylized presentations. This tag frequently co-occurs with tags like 'nakadashi' (internal ejaculation), 'big breasts,' and various body-type tags. Some artists specialize in anal content, developing signature techniques for depicting the act. The tag covers both consensual and non-consensual scenarios depending on accompanying tags.

Mosaic censorship (モザイク) refers to the pixelation or blurring applied to explicit content in Japanese published works. This is due to Japanese obscenity laws that require censorship of genitalia in published materials. The tag helps readers identify whether content is censored or uncensored. Many doujinshi are published with mosaic censorship and later 'decensored' by fans or released in uncensored versions by the artist. Related tags include 'uncensored' and 'full censorship.'

Rape (レイプ) is a content tag indicating non-consensual sexual activity. In doujinshi, this ranges from forceful scenes to fantasy scenarios. The tag is used for content where sexual acts occur without consent from one or more participants. It's important to distinguish this as a fictional content tag — all characters are depicted as adults in the artistic context. The tag frequently appears in darker genres and is often paired with tags like 'bondage,' 'mind break,' and 'dark skin.'