A sadistic fiend who bludgeoned his girlfriend’s helpless 10-year-old son to death in Harlem could spend his remaining years behind bars. Ryan Cato, 38, was sentenced on April 25 to 25 years-to-life for killing Ayden Wolfe — who was subjected to unimaginable abuse while trapped inside his family’s apartment during the pandemic’s early days. “Isolated from teachers and other responsible adults because of the pandemic, 10-year-old Ayden Wolfe was enduring horrific violence at the hands of his mother’s boyfriend,” said Manhattan District Attorney Alvin Bragg in a statement. “Ryan Cato brutally abused him, eventually killing Ayden in his own apartment.” A Manhattan jury in March found Cato guilty of second-degree murder — nearly four years after first responders rushed into a West 131st Street apartment and found an unresponsive Wolfe, bruised and naked. Prosecutors said Cato moved into his girlfriend’s Aquisha Johnson’s Harlem home in January 2021 and quickly began abusing Wolfe. The vicious Cato made Wolfe hold weighs over his head while he repeatedly punched him — and filmed the abuse, sending the videos to his friends, prosecutors said. The abuse apparently escalated March 5, 2021, when loud bangs were heard inside the apartment, as well as Cato threatening Johnson when she yelled at him to stop, officials said. The bangs and thuds continued the next day, prosecutors said. Several hours after the ruckus, Johnson called 911, only to have Cato take the phone from her. First responders arrived to find the naked Wolfe without a pulse, prosecutors said. They rushed him to Harlem Hospital, where doctors tried and failed to save his life. Medical examiners ruled Wolfe’s cause of death to be battered child syndrome. Wolfe had bruises over his body, broken ribs and a slew of internal injuries — a lacerated liver, kidney and renal vein — that caused hemorrhaging. “Some injuries were old, but others were recent,” said then-NYPD Chief of Department Rodney Harrison shortly after Wolfe’s death. Johnson, who had previously been investigated by the Administration for Children’s Services, pleaded guilty to manslaughter and criminally negligent homicide, officials said. She can withdraw her plea to manslaughter as part of a cooperation agreement, according to the officials. Cato was also investigated by ACS for an unrelated case in which he allegedly beat another woman in front of their children, police said. Wolfe’s father gave a heartbreaking victim impact statement read in court by prosecutors during Cato’s sentencing. He said young Ayden was a moral child who made a very big impact on everyone around him. Ayden had a future, which he has no more, he said. 📸: GoFundMe; Michael Nagle; Daniel William McKnight - @nypost