Have to agree, friendly tickling in public isn't wrong. Take care not to exagerrate, though. One example of just that comes to my mind. It was in the underground cart. Rush hours, so it was pretty crowded. There was a couple in their middle twenties nearby and the girl was very pretty. Tall blonde, with great body, wearing tight trousers and sleeveless blouse. I noticed them because I heard her cute laughter. They were about a meter from me, facing each other, so I could clearly see why she was laughing. Her b/f was tickling her ribs and stomach. At first it was playful tickling, but soon it turned to something more heavy and erotic. She was laughing pretty hard then and started to be embarassed, because the whole crowd were staring at them. Besides, he even tickled the sides of her breasts from time to time. She tried to stop him, but couldn't because he was bigger and stronger and because it was too crowded for her to fight. Then she tried to talk him into stopping, telling him it was too public and that his touches are too private in this situationand she was ashamed. He refused to acknowledge. The temptation was too strong for me to avert my eyes, but the situation started to be a bit unpleasant. The girl wasn't enjoying it anymore and obviously felt humilated in front of several dozens people. Finally, the message got through "Don't tickle me HERE!|" she yelled. He anwered "OK, I won't tickle you here." and stopped. It was obvious he will begin again as soon as they come from HERE to THERE. THERE was my station. They emerged in front of me. It seemed like kiss and make up, but I remembered his stressed "HERE" and saw a glitter in his eyes. His arm came around her waist and as soon as they left the station he attacked her ribs. She squatted right theree and howled with laughter. I heard "Don't you understand, I can't take it anymore!". Then she became angry with him, sat on the ground and refused to go till he promised to stop. I had to go, because I couldn't stand and stare so I haven't seen the end of the situation. Of course it was arousing for me but at one point he definitely crossed the line tickling her in so crowded place and refusing to see her humilation.