A sex pest dance teacher has walked free despite sending a set of foul sexualised Facebook messages to two vulnerable 15-year-old girls.

Former high school dance teacher Nigel Major-Henderson pleaded guilty to four counts of communicating to procure a child for sexual activity after the police arrested him for sending obscene digital messages to two teen girls in late 2015 and early 2016 in Adelaide.

In one message he sent to a girl identified by the court as M, Major-Henderson asked her whether she liked the size of her breasts, whether she used them and whether they were annoying.

“Just wear bras, f**k tops, hahaha,” he said.

In messages to a second girl, identified as J, over Christmas in 2015 he asked questions with sexual content in them.

“You turned the discussion to what you described as quote, ‘weird sex things’ end quote’,” South Australian District Court Judge Kristopher Handshin said on Wednesday in his sentencing remarks.

“In was in this context you sent the charged communications to J.

“You told her because of the number of things you had dealt with in the preceding weeks it was helpful for you to be able to get things off your chest by swearing.

“The questions you posed to J were again very childish but they also contained a completely inappropriate sexual inflection and by your plea, you acknowledge that your intention in sending these messages was to have J submit to sexual activity in the form of an electronic communication about sexual matters.”