Hello, thank you for choosing Madmext. According to the measurements you shared, 165 cm height and 54 kg weight, size L will create a very loose and flowing look for you. Due to the natural, light, and breathable structure of muslin fabric, our product already has a comfortable cut. If you do not prefer an overly large (oversize) look, we recommend considering size S for a more balanced and stylish stance according to your measurements, and size M for a slightly loose fit. Size L may be quite wide in the shoulders and sleeves in these measurements. We wish you pleasant shopping. Madmext Team