One of the two blonde English teachers in small-town Louisiana arrested for having sex with the same then-16-year-old male student pleaded guilty to obscenity on Thursday and has thus far avoided prison time. She won’t even have to register as a sex offender.

That’s the good news for the former teacher, Shelley S. Dufresne, reports The Times-Picayune.

The bad news is that she must spend 90 days within the confines of an unspecified mental health facility. (She will also serve three years of probation, pay a $1,000 fine and surrender her teaching license.)

The boy’s mother appeared irate at a court hearing during which Dufresne admitted her actions. At the same time, both parents had “expressed their support for this resolution of the case,” notes the New Orleans newspaper.

In happier days, before the married mother of three was busted for her role in a ménage à trois with an underage boy, Dufresne taught at Destrehan High School in Destrehan, La.

The other teacher involved in the unholy trinity was Rachel Respess, 24.

Dufresne is by no means out of the woods for her exploits. Neither is Respess. They both still face criminal charges for their roles in a threesome with the same, unidentified student.

The charges to which Dufresne pleaded guilty only relate to sex she — and she alone — had with the student.

A separate criminal trial for the threesome could possibly loom on the horizon.

The threesome is what made national headlines, though. And why wouldn’t it? The epic event impressively lasted from 9 p.m. until 6 a.m. the next morning, according to local police.

St. Charles Parish Sheriff’s deputies say the threesome happened on a Friday night, after a high school football game (which Destrehan won easily, 41-7). It was a special night, too, because it was Dufresne’s birthday.

Dufresne “enticed and transported” the student to Respess’s apartment, explains the New York Daily News. Respess, the younger teacher, and the teen had sex. Meanwhile, Dufresne “began intimately kissing” the younger teacher “in an attempt to arouse all parties involved, all who were complete[ly] disrobed.”

Dufresne had been the student’s English teacher this year. Respress had the pleasure of teaching him in English class last year.

The sheriff’s office was tipped off after school officials reported that the unidentified student was bragging to friends about his exploits. (RELATED: TWO Teachers Victimized 16-Year-Male Student With Epic THREESOME)

Both teachers are alumnae of Destrehan High and both graduated from Louisiana State University.

Dufresne’s still-accessible Destrehan High webpage shows she was a 10-year veteran at the school.

Her father is 29th Judicial District Judge Emile St. Pierre, notes The Times-Picayune.

Respess has been an English teacher at Destrehan High for two years.

The school district suspended both Dufresne and Respess without pay around the time police arrested the teachers for their sexual exploits.

As this graphic from Mandatory.com illustrates fairly conclusively, judges tend to find it in their merciful hearts to give lower prison sentences (and often no prison time at all) to attractive female teachers who have sex with underage male students. Ugly female teachers frequently fail to garner such compassion.

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