On request of a fellow here who wants to know more about.
I sometimes do duo modelling with female friends. It is for art groups who want to draw, paint, etc.
There is always physical contact between the 2 models, i.e. me and the friend.
I have done it with 4 different women till now. All 20-30 years younger than me
Some examples. Credits for the drawings and paintings to the respective artists!