Can Ghusl e Janabat become obligatory without ejaculation?

Imam Reza (as) was asked about the man who copulates with a woman nearby the private part but they both do not discharge, When is the ghusl Obligated?

So Imam (as) said : When the two circumcised parts meet, so the ghusl is Obligated.

So it was asked : The meeting of the two circumcised part, is it the glans penis?

Imam (as) replied : Yes.