For the first time the wife agrees to some MFM sharing, there is the getting started introduction. When you invite the other male over or you take your wife to a hotel to meet the other male, your wife knows she going to be fucked by another man. There is a little bit of an introduction, but she knows what's going to happen. She'll be fondled usually by the husband and the other male together. Eventually she'll work with the other male. She' expecting that she'll be sucking his cock. The other male can help her into this by initiating the deed. Presenting his cock so she can get started.
