To answer such a question, one must needs only remember the simple process of elimination.
The first possibility is that Marc tickled me. This, however, is an impossibility since:
a) I do not know anybody named Marc.
b) I am not ticklish.
c) The first male to even thing about tickling me will die a gruesome death. Hey, he wanted me to laugh, right?
It seems clear, therefore, that john tickled josh. What now remains is to find a motive for this crime.
Elementary, my dear Armed.