Being shirtless is more than not wearing a shirt
Have you ever walked around without a shirt? I bet you have. It's something every boy and man does. At start it feels somewhat weird. You feel the lack of weight of your shirt. You can feel the sun and probably notice it's slightly colder in the shade. It feels weird at start, but after a while you start liking it. In fact you want to be shirtless for as long as possible. So why not? Afraid of what others would say or think? It's your life. Don't bother what others tell you to do. Are they always behaving the way you want them to behave? So.., be that shirtless guy. Be a role model for other guys. After a while people will know you as "that shirtless guy" and even expect you to be shirtless.