I work with a buddy and we travel full time sharing hotel rooms. He has caught me masturbating so many times that he just says "go for it" he never does it but I have done it a hundred times in front of him. My older bro never masturbated in front of me but I did while in his car riding home with him I told him I was horny and he dared me to jack off before we got home. I whipped it out and did it. He was shocked but watched. Whenever we share a room I always pull it out and go for it. I have done it in front of about 10 guys who seemed comfortable but haven't done it at same time. Some do it later when I am sleeping or in morning.