A butterfly activitist drugged and strangled her former stepfather after finding nude pictures of herself on his computer, prosecutors alleged.

Thomas Merriman’s body was found in January 2021, under a pile of trash at the Solana Beach, Calif., home he shared with stepdaughter Jade Janks.

The murder trial of Janks, 39, an interior designer who co-founded the research nonprofit Butterfly Farms, began this week in Vista Superior Court.

She has pleaded not guilty to killing the 64-year-old Merriman, who prosecutors said died of an overdose of sleeping pills Janks gave him after she discovered the photos — one of which he reportedly used as his screensaver.

“This was no accident,” San Diego County Deputy District Attorney Jorge Del Portillo said, according to The San Diego Union-Tribune. “This was murder by design.”

The photos were taken more than a decade ago, consensually, by Janks and her boyfriend, authorities said. It’s unclear how they came into Merriman’s possession.

Janks found the photos while she was cleaning her stepfather’s apartment, who had been hospitalized, Del Portillo added.

She texted with another man about giving Merriman the pills, prosecutors contended.

“I just dosed the hell out of him. Stopping for whiskey then at Dixieland to stall. LMK,” Janks allegedly texted the day she picked Merriman up from the hospital, according to Del Portillo.

Janks seems to second guess her plan in another text message the prosecutors shared.

“He’s waking up,” one alleged text read, according to NBC San Diego. “I really don’t want to be the one to do this.”

“I am about to club him on the head as he is waking up,” another read.

Janks eventually called another person for help, said prosecutors. That person called the authorities the next day.

Deputies then searched the home and found Merriman’s body under a pile of boxes, blankets and other trash as they were leaving.

Attorneys for Janks, the argued that Janks did not kill Merriman, who instead died from poor health and “his own cocktail” of drugs.

“You will not find any evidence that he was strangled to death,” Janks’ attorney, Marc Carlos told the jury.