This lora has difficulty in processing sophisticated hair so it's better to have a lower weight and it may do harm to picture quality otherwise.
It's advised to lower cfg and other lora's weight and increase steps to get higher quality.
Maybe using some upscalers would help adressing quality problems,I guess.
Best weight:0.6-1
Trigger words:kitsune,3d
Positive prompts:highres,smooth hair,detailed hair
Negative prompts:blurry hair,messy hair,lowres,2d,anime,illustration