Hearth Drake
A hearth drake is a cat-sized reptile of the Menagerie, dusty sage-green and warm to the touch, with folded wings and a long prehensile tail. Five centuries on Earth have made it the most common familiar in Folk society. It nests on bookshelves and warm hearthstones, hums when content, and bonds to a single person it decides is worth the trouble.
The bond runs both ways and is mostly silent: a hearth drake speaks straight into the mind of the one it has chosen, in simple pushes of feeling and image rather than words. Folk families pass them down through generations, and more than one Nawadzi School for Forgotten Folk student has smuggled one into the dormitories rolled up in a coat sleeve, which the faculty pretend not to notice and the wards are specifically tuned to allow.
They are harmless to those they like and a genuine nuisance to those they don't, with a sting that puts a grown adult to sleep where it stands.
Encountering one
A hearth drake left to itself is shy, clever, and very hard to surprise. Bonded ones share their senses with their person, which makes them superb early warning: a drake that goes rigid and silent has seen something its companion has not. They fight only cornered, and prefer to sting and flee.
Statblock
Mechanically a reskinned Pseudodragon. Run it straight from the SRD; only the name and flavor change.
Tiny dragon neutral good
Armor Class 13
Hit Points 7 (2d4 + 2)
Speed 15 ft., fly 60 ft.
Skills Perception +3, Stealth +4
Senses blindsight 10 ft., darkvision 60 ft., passive Perception 13
Languages understands Common and Draconic but can't speak them
Challenge 1/4
Keen Senses. The hearth drake has advantage on Wisdom (Perception) checks that rely on sight, hearing, or smell.
Magic Resistance. The hearth drake has advantage on saving throws against spells and other magical effects.
Limited Telepathy. The hearth drake can magically communicate simple ideas, emotions, and images telepathically with any creature within 100 feet of it that can understand a language.
Actions
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 ( + 2) piercing damage.
Sting. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 4 ( + 2) piercing damage, and the target must succeed on a DC 11 Constitution saving throw or become poisoned for 1 hour. If the saving throw fails by 5 or more, the target falls unconscious for the same duration, or until it takes damage or another creature uses an action to shake it awake.