Stirge

Tiny beast, unaligned

Armor Class 14 (natural armor)

Hit Points 2 (1d4)

Speed 10ft., fly 40ft.

Senses darkvision 60ft., passive Perception 9

Languages -

Challenge 1/8 (25 XP)

Actions

Blood Drain

Melee Weapon Attack: +5 to hit, reach 5ft., one creature.
Hit: 5 (1d4+3) piercing damage, and the stirge attaches to the target. While attached, the stirge doesn't attack. Instead, at the start of each of the stirge's turns, the target loses 5 (1d4+3) hit points due to blood loss.

The stirge can detach itself by spending 5ft of its movement. It does so after it drains 10 hit points of blood from the target or the target dies. A creature, including the target, can use its action to detach the stirge.