HILO >> A Hawaii man who prosecutors say fatally shot his girlfriend and her mother with a shotgun — while two children were in the house — was sentenced to life in prison with the opportunity for parole after 15 years.

The daughter and granddaughter of the two victims, Taiana Ahu, appeared in court for Sean Ivan Masa Matsumoto’s sentencing, pleading with the judge to “do the right thing” and sentence him without parole. But Judge Greg Nakamura stood by the agreed-upon plea deal.

Matsumoto pleaded guilty in June to two counts of second-degree murder and use of a firearm in the commission of a separate felony for the 2013 double killing of Rhonda Ahu and her mother Elaine Ahu, The Hawaii Trib­une-Herald reported Thursday.

He had a first-degree murder charge dropped, which carries a mandatory sentence of life without parole upon conviction, as part of the deal.

Deputy Prosecutor Kelden Waltjen noted the sentence in the case was “preordained” before describing Matsumoto as “a selfish, coldblooded killer who should spend the rest of his life behind bars.”

“That night, the defendant took his black, pistol-grip Mossberg 500 12-gauge shotgun and shot Rhonda in the head while she was sitting on their recliner in the living room. She was still holding her television remote control in her hand when her body was found by the police,” Waltjen said. “He (then) walked down the hallway, peered into Elaine’s room where she lay asleep on her bed, next to her grandson, the defendant’s own 6-year-old son. This time the defendant wanted the victim to see what was coming. He fired a single shot toward the bedroom ceiling to wake Elaine up. This was personal.”

Stanton Oshiro, Matsumoto’s court-appointed attorney, said the prosecution and defense “differ in our view of what happened that evening.”

“Clearly, no one was there other than Mr. Matsumoto, the decedents and the children, who were asleep at the time,” Oshiro said. “This case took a long time to resolve because there were many complicated issues, primarily regarding Mr. Matsumoto’s mental health and his problems therein.”

Given his chance to address the court, Matsumoto said, “All I just wanted to say is I’m sorry.”