What is the ruling on tattooing to cover gaps in the mustache for cosmetic and psychological reasons?

Tattooing is forbidden for both men and women, and it is considered one of the major sins due to the curses mentioned concerning it. It is not permissible to do it for adornment or to improve one's appearance. As for sparse beard and mustache hair, if it is bothersome and causes embarrassment, it is permissible to treat it with a permanent, pure dye, or with hair transplantation. This is not considered changing the creation of Allah, but rather a form of treatment. However, tattooing by inserting needles and trapping blood is not permissible due to the prohibition against it, and because it renders the tattooed limb impure.