blood fairy

Stick. Melee Unarmed Attack: The blood fairy can choose one creature within 5 feet and the creature must succeed a DC 12 Dexterity saving throw or the blood fairy is stuck onto the target. Once stuck, the blood fairy does 1 piercing damage to the target at the beginning of each of the target's turns and has disadvantage on dexterity saving throws. If the blood fairy is stuck to the targets back the blood fairy gains 2 AC. 

Suck with fey poison Melee Weapon Attack: once stuck this attack is guaranteed to hit the target it is stuck to. Hit: 3 piercing damage and the blood fairy gains 2 temp hp, and the target must succeed on a DC 10 Constitution saving throw or become poisoned for 1 minute. If its saving throw result is 5 or lower, the poisoned target falls unconscious for the same duration, or until it takes damage from another creature or another creature takes an action to shake it awake.

Invisibility. The sprite magically turns invisible until it attacks or casts a spell, or until its concentration ends (as if concentrating on a spell). Any equipment the blood fairy wears or carries is invisible with it.