tl;dr short, heartwarming forbidden-yuri romance with mostly realistic story-telling and poignant moral lessons. Big recommends!
On the surface level, Kakeochi Girl is not too shallow, but also not too deep. However, if you put yourself in the shoes of the characters and really internalize how they might feel, it becomes much deeper and much more rewarding.
Makimura "Maki" Momo and Oonishi Midori were high school lovers that never really explored their sexuality until graduation when Midori essentially breaks it off, saying it was fun but it's time to pursue normal lives. The two don't see each other again until a fateful encounter 10 years later. Maki is still taking graduate courses while living with her mom and lamenting her loneliness, while Midori is engaged and pregnant and living that perfect, normal life she wanted. It goes without saying that such matters aren't so simple, and that's what the next 15 chapters explore.
Overall, my enjoyment was enhanced as I really related to Midori's feelings about herself and about life, but the story is still objectively solid. Certain things could have played out differently, but I chalk that up more to the characterization. That's my one real knock on this series, that Maki doesn't really get explored much beyond her relationship with Midori, and Tazune, Midori's fiance, is more of a plot device than a character. I'd care less about Tazune if he was the faceless salaryman stereotype, but Battan tries to give him characterization and parts of that just fall totally flat.
Given the length and quality of the story, this is a strong recommend as you can easily knock this out in an afternoon and shed a few tears along the way.