Vampire’s Bite

The caster’s canine teeth grow into fangs, and the caster makes a melee spell attack to plunge their teeth into any exposed skin the target possesses (preferably the neck).  On a hit the caster deals 1d8 necrotic damage and the target must make a CON saving throw.  On a fail, if the target has blood, the caster gains temporary hit points equal to half of the damage dealt.