This work is considered secondary-canon. Although it has not yet been removed from the Robotech universe, it is still not considered Primary Canon. See Continuity and Canon in the Robotech Universe. |

Karl Riber was the fiance of Lisa Hayes. He was stationed at Mars Base One as he was a gentle young man. during the Global War, he and Lisa were out in the rain by the school and he liked a song made by Lory. They returned to the school to find Lory who told them classes were cancelled due to an airstrike warning. Lory bickered with Lisa over Lory watching her and Karl for inspiration for her love songs but Karl noticed a sound and they ran as the school was hit with Missiles (Robotech: Return To Macross: Love In A Memory)
Despite getting no word from him, Lisa often wrote to him in her diary to deal with her feelings (Robotech: Academy Blues).
Years later, she kept a photo of him, even up to her marrige with Rick Hunter and the Pioneer Expedition. (Robotech II: The Sentinels Wedding Special 1: Wedding Day')