Karin-san, Tsujitsuma ga Aimasen!

Sabae Karin has always been pretty and popular, but for some reason, she's never been able to get together with anyone she likes. Now at the age of 37, she's ready to put it all on the line! Due to a misunderstanding, Yuzu Mikawa (31), the man she fell in love at first sight, thinks she's 25 years old. And now she is going on to the stage of love pretending to be a girl a whole zodiac cycle younger than her real age...

(Source: Jour Comics)