Vampiric Bloodline

There are many reasons for why someone would possess vampiric blood. Perhaps you're descended from a long line of people with vampiric blood, or perhaps an ancient vampire performed a dangerous ritual, letting you feed of their blood and gain the powers of the night for yourself. Perhaps an encounter with a vampire left you bitten and bloodied, and the magic that permeates their blood began to engulf you, transforming your body and giving you powers similar to those of a vampire. For whatever reason your blood has been tainted with vampiric magic, and you've learned to tap into it.

Vampiric sorcerers most often try to hide their nature, since, if they aren't careful, it can make them as reviled as the vampires they derive from. However, a select few embrace their vampiric abilities, and may even seek to become true vampires. Your vampiric blood allows you to tap into all the powers of the night, controlling animals, blood magic, charming people and a physical body far beyond that of mortals.

Denizen of the Night

Starting at 1st level, you have darkvision with a range of 120 feet.

You gain the ability to bite people with your sharp teeth and drain their blood. As a bonus action you can make an attack against a creature that's restrained, grappled, incapacitated or charmed by you. This attack is considered a natural weapon and a simple melee weapon, you're proficient with it, and it uses your Charisma modifier for the attack and damage rolls instead of your Strength modifier. On a hit it deals necrotic damage equal to 1d6 + your Charisma modifier, and you gain temporary hitpoints equal to the necrotic damage dealt.

Unnatural Charisma

Starting at 1st level, you can beguile and influence the minds of people around you. You gain proficiency in the persuasion skill if you don't have proficiency in it already. You can cast the charm person spell an amount of times equal to your proficiency bonus without expending a spell slot. Charisma is your spellcasting ability for this. You regain all uses of this ability after a long rest. 

Power of the Night

Starting at 6th level, when you cast a sorcerer spell that deals necrotic damage, you add your Charisma modifier to one necrotic damage roll of that spell or attack against one of its targets.

In addition, your bite attack now deals necrotic damage equal to 1d8 + your Charisma modifier instead of 1d6 + your Charisma modifier.

Children of the Night

Starting at 14th level, once per day, as an action, you can expend a Spell Slot of 3rd level or higher, and magically call 2d4 swarms of bats or swarms of rats, provided that the sun isn't up. While outdoors, you can call 3d6 + 2 wolves instead. The called creatures arrive in 1d4 rounds, acting as your allies and obeying your spoken commands. The beasts remain for 1 hour, until you die, lose concentration (as if you were concentrating on a spell) or until you dismiss them as a bonus action.

You gain a semblance of the regenerative abilities of a vampire. At the start of each of your turns if you are at or below half of your maximum hitpoints and have at least 1 hit point, you regain a number of hit points equal to your charisma modifier. You don't regain hitpoints from this ability when you're in sunlight or running water.

Vampiric Form

Starting at 18th level, you can spend 10 sorcery points as an action to cast the shapechange once per day. The only form you can adopt with this casting of shapechange is that of a vampire, ignoring the normal restrictions on the shapechange spell that would prevent you from adopting the form of an undead. You also do not have to have seen a vampire to adopt its form using this casting of the shapechange spell.