Police arrested Arthur Romero, 62, Tuesday after his granddaughter told her parents she had been molested by the man at his Buckeye home.
The girl told the cops she has been sexually abused by Romero since she was in second grade.
According to court documents obtained by New Times, the girl gave an extremely graphic description of being molested by her grandfather.
She told police that, on several occasions, Romero pulled her pants down and would insert his fingers into her vagina and anus.
Other incidents she described involved using her hand to stroke his crotch, and also rubbing her breasts underneath her shirt.
The girl's mother called Romero to confront him about molesting his granddaughter.
Romero told her that he "drinks a lot" and didn't remember doing any of it, but was also "sorry and wished he could take it all back."
After police arrest Romero Tuesday, he told them he didn't remember molesting the girl, but wasn't sure it didn't happen.
He told police about his heavy drinking, saying he "does not always remember what happens when he is drunk."
Romero said he couldn't give any other explanation to the girl's molestation, but said there was no reason why his granddaughter would fabricate her stories.
Romero was booked into the Fourth Avenue Jail, where he awaits charges of sexual conduct with a minor, sexual abuse, and molestation of a child.