''20-Year-Old Girl X 30-Year-Old Maiden'' is a GirlsLove manga by Creator/AkikoMorishima that’s ExactlyWhatItSaysOnTheTin — a romance between a 20-year-old student, Emi, and her 30-year-old teacher, Keiko, focusing on how the age gap affects their relationship.
!!This manga provides examples of:

* BishieSparkle: Emi, constantly.
* ChristmasCake: Keiko, and it causes her a lot of anxiety when she compares herself to 20-year-old Emi.
* ClingyJealousGirl: Emi goes through a phase of this.
%%* FuroScene
%%* GirlsLove
* GoodBadGirl: Kazue. She even had a threesome with two guys once!
* LoveAtFirstSight: Keiko and Emi. They even have debates over who fell for whom first.
* NoPeriodsPeriod: Averted. In one chapter, Emi’s period ends up foiling Keiko’s plans to deflower her.
%%* OdangoHair: Youko.
* OneeSama: Referenced by [[YuriFan Youko]], who identifies Keiko as both this and the {{Seme}} because she’s the older one in the relationship.
* {{Ronin}}: Emi is on her third attempt at getting into art college.
* TaremeEyes: Kazue.
%%* TeacherStudentRomance
* ThoseTwoGuys: Youko and Kazue, Keiko’s OddCouple roommates.
* YuriFan: Youko. She even makes a couple of [[ShoutOut Shout Outs]] to Marimite.