[Hiiro no Kenkyuushitsu (Hitoi)] Enkou Kanojo to Kengakukai [Digital]

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.

Nakadashi (中出し) literally means 'internal ejaculation' and refers to creampie scenes in doujinshi. It's one of the most common sexual act tags, appearing in over 120k galleries. The tag covers vaginal internal ejaculation specifically. In narrative terms, nakadashi often serves as a climactic moment and may be tied to plot elements like pregnancy, impregnation, or relationship escalation. Artists frequently emphasize the visual aspect with detailed internal views (often using x-ray techniques). Related tags include 'impregnation,' 'creampie,' and 'internal cum shot.'

Blowjob (フェラチオ, fellatio) is one of the most common sexual act tags in doujinshi. It covers oral sex performed on male characters. The artistic depiction varies from realistic to stylized, with many artists developing signature techniques for depicting the act. Common visual elements include drool, tongue detail, eye contact, and depth indicators. The tag appears across virtually all genres and is frequently paired with tags like 'ahegao,' 'big breasts,' and 'sole female.'