Ms. Koizumi Loves Ramen Noodles

Koizumi-san is a reserved and mysterious high school girl. Her classmate Ohsawa Yuu is very interested in this new transfer student. One day on her way home, she happens to see Koizumi-san in a long line in front of a ramen shop, which leads to them eating ramen together, and yet...

Nakamura Misa was supposed to go on a date, but instead her boyfriend dumps her without giving her any recourse. Misa spots Koizumi-san walking by and shadows her, thinking that she might have seen the embarrassing scene. Her destination seems to be a red ramen shop specializing in extremely spicy ramens...

Once again, Koizumi-san cooly declines Yuu's invitation to go eat together, but giving up is not Yuu's style. The two of them actually meet at a ramen shop, but it's jam-packed and there are single seat cubicles and Koizumi-san could not be further away! However, Yuu's going to have her moment in the sun where she gets to flex her cooking chops...

One day, Koizumi-san leaves school saying that she has something to do. Yuu is doesn't think anything of it, sure that she is talking about ramen again. But of course, Yuu tails her again, and she sees Koizumi-san waiting for someone in front of a fancy western restaurant. When a dashing man appears she yells "Koizumi-san, don't!"

In today's science class, the four girls learn about the 'green bug' which is known as euglena. Brimming with scientific curiousity, Jun can't stop wondering about what that might taste like, and agrees to go have euglena ramen with Koizumi-san. What is that absolutely foreign flavor going to be like???

The summer heat is on! Koizumi-san looks at the trio loudly suffering from the heat with disdain while she continues on her ramen pilgrimage. Yuu wills herself to follow her, and Koizumi-san declares that she will be having "hiyashi" ramen. What exactly is this "hiyashi" ramen?