Blood Oath

The target of the spell draws the knife across their palm, willingly binding themselves to the caster. The target suffer 1d4 damage, reducing their hit point maximum by that amount permanently. The target must always follow instructions of the one they bind themself too. If they ever fail at following an order, their blood begins to boil for each minute they fail to complete the instructions. Each minute they take one hit die of unreducable damage and reduce their hit point maximum by that amount as well. If their hit point maximum is reduced to 0 the dissolve into a puddle of blood.