In the Netflix's Sense 8, Wolfgang kills his father as a boy. Later, when grown up, he pisses on his father's grave. What is the reason for doing all of this?
Because he was abusive.
Anton Bogdanow is the father of Wolfgang Bogdanow. He is abusive towards his son. He said that there are only five things that are important in life: eating, drinking, shitting, having sex and fighting for more. Because of the physical and verbal abuse he inflicted upon the young Wolfgang, his son strangled him to death.Source
From the character Wikia
According to Wolfgang, the resentment towards his uncle come from the fact that his uncle was aware of his father's abusive behavior, yet did nothing to stop it.
Wolfgang had a flashback from when he was a child, standing in front of an audience and nerving himself to sing. He watches as his father Anton watches from the back and smiles, and then breaks out into laughter as Wolfgang freezes.
Felix suggests Wolfgang to sing and he does. Before he sings, Wolfgang recalls a memory of his father laughing at him and curses loudly with the crowd cheering him.
Before violently shooting his uncle at close range in the face, he admits he killed his father. Recalling his uncle's pleas to recognize their shared blood, Wolfgang states that the blood that runs in his uncle's veins also ran in his father's veins--and just as his father was a monster, so is his uncle, and so is Wolfgang himself.