Step-sister sucks dick... so she doesn't get in trouble

A strict father closely monitors the behavior of his daughter and stepson, not allowing them to even think about sex or anything like that. And then the guy walks into his stepsister's bedroom and sees her masturbating. This is a reason to call her father and tell him everything, receiving praise from him. But what could convince him not to do that and keep everything a secret? Of course, it's a sweet blowjob from his stepsister.