trigger word : koyanagi_rou, dark blue hair, grey hair, asymmetrical bangs, yellow eyes, blue eyes, multicolored eyes, hair ornament
optional : blue hair, short hair, ear piercing, yellow eyeshadow, hand tattoo, black nails
official costume : fur-trimmed jacket, black shirt, long sleeves, denim
official costume (optional) : choker, bracelet, ear piercing, necklace, ring, glasses
otomo : otomo_cat, stuffed toy, cat, etc... (If you don't want them, type in the negative prompt.)
It would be better if you put 'arm tattoo' on the negative.