Does anyone know the name of a manga where two childhood friends, a boy and a redhead girl, are engaged. Besides the boy was always her friend because she was very shy but when they grow, they grew apart from each other because he was popular but she wasn't. In addition, she finds him having sex in the gym and after that she changes completely.
I remember that there was a leap in time where we see they are college graduates and she's all serious and tries to break their engagement because he hates him.
Also, the boy was blonde and the girl always wear braid and glasses when she was younger.

Also, the boy was blonde and the girl always wear braid and glasses when she was younger.

This sounds quite interesting. Do you remember if it's a oneshot or has a few volumes? And completely scanlated?

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