He is the father of Ayano Aishi and the husband of Ryoba Aishi.
Since Yandere-chan's father's appearance has never been fully revealed, it is unknown exactly what he looks like. The only thing that is known about his appearance is that he looks like an adult version of the default Senpai.
His personality is unknown.
Ryoba Aishi - It is never said that he loves his wife. Ryoba kidnapped him and held him hostage in the basement. Later on, they got married and had Ayano.
Ayano Aishi - He knows that Ayano is emotionless and finds her strange, but he loves his daughter regardless.