Tenchi Muyô! In Love

Tenchi and co. find their existence unsettled by a time-travelling entity called Kain. Desiring revenge upon the Juraian emperor, Tenchi, Kain travels back in time to kill Tenchi's mother. Trying to preserve the timestream, Tenchi and friends follow him back. Unfortunately, Tenchi must also deal with the pain that seeing his mother causes him. Since she died in the future, seeing her alive in the past reopens his old wounds.