Todd Blauvelt Jr., 18, of Gorham, N.Y., was arrested and arraigned after the home's rightful owners found him, his 15-year-old girlfriend and her family in the house in South Bristol, N.Y., state police said.
He had allegedly convinced the girl and her family he had inherited the 6,000-square-foot house from his deceased grandfather and invited them to move in with him, investigator Mark Eifert said.
Blauvelt also described the fictitious inheritance story in a signed deposition, Eifert told the Democrat and Chronicle of Rochester, N.Y.
He was charged with second-degree burglary and writing a false written statement and was jailed in lieu of bail or bond, Eifert said.
It was not clear why Blauvelt picked that house, Eifert said.
The girl and her family were not charged because it appeared they did not know his inheritance story was false and therefore did not commit a crime, Eifert said.
Blauvelt also faces charges of sexual misconduct and endangering the welfare of a child after being accused of having sexual contact with his girlfriend, police said.