Challenge yourself! Dress up as you feel maximum shame, wear ballgag, tight corset, nippleclamps, add magic wand with random timer, blindfold yourself and use 5 fingertraps behind your back. Left a knife and scissors into another room. Let your friend check you after 1 hour from start. I guess, you will not escape, and he will find you being crying from pain in nipples.

If it happens - give him right for take some pictures and one wish as payment for help to get free but condition: let him sound a wish only after one week. You will burn by unknowness - what did he come up with?
P.S. Important: don't test possibility of escape before game starts, or it will not be a challenge. The fear that it might be impossible to get out is an important part of the game, and without it there will not be half the fun of the challenge. The main thing is that a friend turned out to be reliable.
P.P.S. If you are brave enough, let him take advantage of your helplessness and play with you in any way he wants.
Not all dreams must come true. Choice with a cold mind. Be careful. Not crazy as me.