Deene Juncker, a former teacher, pleaded guilty in King County Superior Court on Tuesday to two counts of second-degree sexual misconduct with a minor.

The 47-year-old former teacher at Forest Ridge School of the Sacred Heart was arrested in November after authorities said he had sexual relations with a 16-year-old female student.

Questions about his relationship with the student were raised by the mother of the girl. The mother and the head of the school met with Juncker and warned him against sending text messages to the girl outside school hours, according to the probable-cause document.

On Oct. 22, the Bellevue Police Department was notified and began an investigation.

The investigation uncovered an ongoing relationship between Juncker and the girl which started last summer. The two stayed together at a Bellevue hotel in September.

After resigning from Forest Ridge School in October, Juncker started working as a sales clerk in a comic-book shop.

According to Dan Donohoe, the spokesman for the King County Prosecutor’s Office, Juncker faces between 15 and 20 months in prison when sentenced on June 26.

Lindsay Larin can be reached at 425.453.4602.