A Blood Oath is a Sworn Word which is reinforced with both Essence and the spark of life itself – blood. This intense bond allows a compact to be made rapidly, with little or no understanding or indoctrination. A ‘blood-compact’ may be sacred one to a Divine Principle or any entity which is capable of granting power. Some oath is made in service of the other. Typically this is for some benefit of the swearer – be it immediate and material or simply reinforcing their depth of character. If foresworn, the oath-breaker jeopardizes their own Sanity in addition to normal penalties for oath-breaking (Mark of Tovik (armaments of Law) an act of Transgression). The Blood Magic tradition provides for a means to enable a Blood Oath between a Fiendish entity and Divine Principle to support a Compact of Dark Shelter. The cementing of the compact is always done through a offering of Blood and Souls. The breaking of the compact triggers a violent and harsh Transgression.
This presents a good opportunity for adding Character Story elements to the Character.