A Denison Middle School teacher has been arrested, accused of having an inappropriate relationship with a student.

"Wednesday afternoon around 1:30," said Denison Police spokesperson Lt. Mike Eppler.

That's when Denison Police said they arrested Tharon Lance Day at his home off Woodlawn Circle, formally charged with an improper relationship between an educator and student.

The investigation began a few months ago when a school employee called police.

"It's very serious, of course it's a felony charge," Lt. Eppler said.

The student told investigators they started chatting while preparing for bible study with the group Fellowship of Christian Athletes. Shortly after, the student said they exchanged naked pics after Day asked for nude pictures over the social media app Snapchat.

Investigators asked coach Day if that was true and according to court records he said he "wouldn't deny it" and when asked if he sent pictures of his erection he said "I ain't sending no softie".

Both admitted to talking about having sex but both say they only ever hugged.

Day told investigators he has a "little sex demon" that lives inside him and it got the better of him.

"Teachers are expected to take care of the students and it's taken very seriously with everyone if something like this happens,"Llt. Eppler said.

We spoke with Day outside his home in April. He told us the two were never physical and that it was all a misunderstanding.

"We highly encourage parents to always keep a line of communication open with their children about anything," Llt. Eppler said.

Denison ISD said Day resigned shortly after the investigation started and if convicted, he could get 20 years in prison.