Blood leech

 as a bonus action, you make a spell attack on hit you do 2d6 necrotic damage to your target and siphon their blood to regain 1d6 + spell modifier to your HP or you may choose a willing creature within 10feet of you to heal instead of yourself. you do not regain any Hp from targets that do not have blood.  you may not heal any targets that do not have blood either such as undead allies, warforged and other creatures without blood. 

For every spell slot level above 1st you cast add 1d6 necrotic damage and restore an additional 1d4 HP.