I was seduced by my cabin mate on my first trip to sea. I was a 16 year old cadet and shared a cabin with the senior cadet who was 19. I was probably what would be called a pretty boy then, blue eyes , fair hair and a hairless body. Ship was trading in the far East, very hot and in those days no aircon. O ff duty we sat around in just underpants or with a towel wrapped round us. We got on quite well we chatted , smoked or read a book. The talk would quite often turn to sex and that would sometimes give me an erection, not easy to hide when wearing just a towel or a pair of underpants, My senior soon realised that sex talk could arouse me and it amused him to watch me move about trying to hide my condition. One night when I was erect he pulled the towel off me and there I was naked with percy pointing the deckhead. After that it became a sort of game between us getting me stiff then pulling my pants down or grabbing the towel. I have stopped it but possibly I was seducing him rather than he , me. One night things changed, My senior had turned in and soon after I got up to put out the cabin light, then went to the bunks to turn in myself. I had the top bunk and in order to get in I had to put a foots on the edge of the bottom bunk to help me up. As I got to the bunks, an arm snaked out and grabbed me round the waist and hauled me in to a semi sitting position in the lower bunk. My senior was bigger, older and stronger than I was and in this awkward position I did not have much purchase.. My senior then told me to masturbate him, I refused so he pushed his free hand into my pants and fiddled with my dick which soon became hard. I tried hard not to cum but it was no use, he made me shoot my load into my pants, then said are you going to wank me now, I refused again, he continued to fiddle wit my cock keeping it hard and in a short while he made me shoot again in my pants, he laughed and told me to go and get cleaned up at the basin, I took off my soaking underpants and sponged myself at the basin then turned in. Next morning both of us just behaved as though nothing had happened.