センにおしおきしてくださいにゃ。

Sole female indicates that a gallery features exactly one female character throughout the entire work. This tag is important for readers who prefer focused, intimate scenarios rather than group dynamics or harems. It doesn't imply anything about the number of male partners — a sole female gallery can feature one male partner (sole male) or multiple. The tag helps distinguish between different relationship dynamics and is commonly paired with tags like 'sole male' for one-on-one scenarios or 'multiple male' for gangbang-type content. In terms of narrative structure, sole female works often develop a single relationship or encounter in depth rather than juggling multiple characters.

X-ray (X線) is a visual technique tag where the artwork shows internal anatomy during sexual acts. This allows viewers to see internal ejaculation, penetration details, and other anatomical elements that wouldn't be visible in a normal perspective. The technique is unique to illustrated content and is a significant artistic choice. It frequently appears alongside 'nakadashi' and 'impregnation.'

Dark skin (黒人, kokujin / 日焼け, hiyake) refers to characters with darker skin tones. This includes naturally dark-skinned characters, tanned characters (tanlines), and characters with dark skin as an artistic choice. The tag covers various ethnicities and skin tones. It's often paired with tags like 'tanlines,' 'big breasts,' and 'big ass.'