KIRARA

Twenty-four-year-old Kirara is on her way to her wedding when she is killed in a car accident. However her love for her fiance is so strong that she is permitted to return to earth as a ghost to see him. But she is sent back 8 years in time, to when she and her fiancé first met. However her own meddling in the past may make her 16 year-old-self turn away from her would-be fiance. — Description from AniList community (anilist.co).