Ubuna Katabutsu Shodouka wa Okute na Kanojo to Koi ni Oboreru

After her childhood friend, whom she thought of as her boyfriend, decided to marry someone else, Haruka wanted to get back at him. So she signed up for a calligraphy dating mixer. When Haruka got some unwanted attention from another attendee, she was rescued by Eiyuki, the handsome calligraphy instructor. (Source: Renai Tengoku, translated) *Note: Chapter count includes a volume-bonus chapter.*