Plaguelouse Larva
Source: Vendor. A parasite that latches onto some of the larger beasts of Maldraxxus and drinks until fully-grown, one wonders how the beasts don't manage to notice. Critter type.
Plaguelouse Larva is a Shadowlands pet obtained through Covenant-specific activities that require reaching Best Friend status with your Covenant.
Guide awaiting review
Choose your Covenant path
Select one of four Covenant acquisition methods: Night Fae requires using 2 
Wildseed Root Grain on any quality 
Martial Spirit for a chance at the pet. Venthyr requires 
RSVP: Baroness Vashj at Best Friend to earn the pet from the Baroness Vashj tribute chest. Kyrian requires defeating Mad Mortimer on Wisdom difficulty. Necrolord requires constructing Atticus at your Abom Stitching yard.
Purchase from Covenant vendor
Once you reach Honored status with your Covenant, purchase Plaguelouse Larva from the Covenant vendor for 
1000 Reservoir Anima.
