Tends to generate black gloves and neckwear like in his hero outfit so put - hero outfit, neckwear, gloves, on negative prompt, if you want different clothes
Start with score_9, score_8_up, score_7_up, Sen Kaibara, official style, my hero academia, 1boy, solo, <lora:Sen_Kaibara:0.8>, black hair, spiked hair, black eyes, then whatever you want