In Japan, there is still immense stigma that surrounds tattoos. This stems from the use of tattoos to mark prisoners and criminals in ancient times, and also from the use of tattoos by the Japanese mafia, called the 'Yakuza'. A lot of businesses like gyms, saunas, etc., still ban customers with tattoos even today.
The Oni mask is often the centerpiece of Horimono (full body tattoo). The Horimono can take years to complete, and is normally done in weekly sittings. This makes it extremely expensive. Traditionally created by almost carving the tattoo, the sheer pain, time, and effort of this tattoo signifies the person's dedication and strength.