Zuru Sugiru Kimi ni Futatabi Oboreru

Ten years after a painful first love, Ayumi now lives a stable life with a boyfriend she considers marriage material. Though she occasionally remembers her first love, Koudai, the memories no longer hurt like they used to. She assumes life will continue this way—quietly enduring the stress of work—until Koudai suddenly reappears before her as the company’s new vice president. Their fleeting summer romance from years ago begins to resurface, and just like before, his teasing yet sweet behavior leaves her defenseless against him once again. Original Webtoon