Tohno

Suzerain of all the “demon hybrids” living in the region where Tsukihime takes place. Perhaps because of their long history, the Tohno and all their numerous branch families are quite wealthy, and together make up a prominent business conglomerate.
Going purely by financial power, the Tohno are actually beaten out by the Kugamine branch family. However, to these people blood is more important than anything else, and as the inheritors of the most precious blood of all, the Tohno family naturally fell into a leadership position.
Allegedly, they are the descendants of a powerful family that intermingled with oni (not kishin—humans that became oni—but actual, born and bred oni) and ruled the land for generations.

Tsukihime Data Collection: Tsukihime Dictionary
§

Suzerain of all the “demon hybrids” living in the region where Tsukihime takes place.
Perhaps because of their long history, the Tohno and all their numerous branch families are quite wealthy, and together make up a prominent business conglomerate.
Going purely by financial power, the Tohno are actually beaten out by the Kugamine branch family. However, to these people blood is more important than anything else, and as the inheritors of the most precious blood of all, the Tohno family naturally fell into a leadership position. Allegedly, they are the descendants of a powerful family that intermingled with oni (not kishin—humans that became oni—but actual, born and bred oni) and ruled the land for generations.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
§

Suzerain of all the “demon hybrids” living in the region where Tsukihime takes place.
Perhaps because of their long history, the Tohno and all their numerous branch families are quite wealthy, and together make up a prominent business conglomerate.
Going purely by financial power, the Tohno are actually beaten out by the Kugamine branch family. However, to these people blood is more important than anything else, and as the inheritors of the most precious blood of all, the Tohno family naturally fell into a leadership position.
Allegedly, they are the descendants of a powerful family that intermingled with oni (not kishin—humans that became oni—but actual, born and bred oni) and ruled the land for generations.

MB Act Cadenza PS2 Manual: Tsukihime Dictionary