Found the game it comes from: http://www.getchu.com/soft.phtml?id=574705

"年上Lesson～義母と叔母と女教師と～ スペシャルプライス版" "My aunt and mother-in-law and the older woman Lesson ~ special price teacher edition"

Apparently, this woman is a teacher.

surveyork said:
Apparently, this woman is a teacher.

On what subject?

Hopefully, oral history.

dkdb said:
On what subject?

A sex teacher.