A serious amateur wife is deceived, and two pieces that are persuaded by husband's acquaintance and fall into the sex sex

My wife is very serious, she has a hard side, few friends, and only a partner is my husband. Then, I introduced my male friend to my wife and thought that I could solve my wife's stress even if I could talk with others. However, in the back of the act which seemed to be the gentle consideration, there was my dark desire.