Nuppeppo ぬっぺっぽう

Medium ooze (yokai), neutral

Armor Class 12 (natural fat)

Hit Points 65 (10d8 + 20)

Speed 20 ft.

STR 14 (+2) · DEX 8 (−1) · CON 14 (+2) · INT 6 (−2) · WIS 10 (+0) · CHA 8 (−1)

Skills Stealth +1, Survival +2

Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks (due to rubbery flesh)

Condition Immunities charmed, frightened, prone

Senses darkvision 60 ft., passive Perception 10

Languages — (understands but does not speak)

Challenge 4

Traits

Stench of Decay. Any creature that starts its turn within 10 feet of the Nuppeppo must succeed on a DC 14 Constitution saving throw or be poisoned until the start of its next turn. On a successful save, the creature is immune to the Nuppeppo’s Stench of Decay for 24 hours.

Amorphous Bulk. Nuppeppo’s body is a mass of saggy folds. It can move through a space as narrow as 1 foot wide without squeezing. When it does, it leaves behind a greasy residue that lingers for 10 minutes, making the area difficult terrain for creatures other than the Nuppeppo.

Non-Aggressive Nature. The Nuppeppo does not initiate combat or attempt to harm creatures unless it is severely provoked (e.g., attacked, cornered, or captured). In most cases it will try to lumber away at half speed if threatened.

Strange Flesh (Optional). Legends say consuming the Nuppeppo’s flesh grants eternal life, though the truth (and side effects) remain uncertain. Should a creature manage to kill the Nuppeppo and devour its rancid tissue, the GM might allow a one-time boon (e.g., immunity to disease or aging), paired with a severe curse or transformation.

Actions

Flabby Slam (Only if Forced). Melee Weapon Attack: +4 to hit, reach 5 ft., one target.

Hit: 9 (2d4 + 4) bludgeoning damage plus 3 (1d6) poison damage (the Nuppeppo’s rancid oils seep into the wound). If the target is poisoned by the Nuppeppo’s Stench of Decay, it also has disadvantage on this saving throw to avoid further poison effects.

Belly Flop (Recharge 5-6). The Nuppeppo flattens itself and flops forward. Each creature within a 10-foot cone must succeed on a DC 14 Dexterity saving throw or take 13 (3d6 + 3) bludgeoning damage and be knocked prone. On a success, a creature takes half damage and isn’t knocked prone.

Reactions

Repulsive Quiver. When the Nuppeppo takes damage from a melee attack while within 5 feet of it, it can use its reaction to cause its flesh to shudder violently, releasing a fresh wave of stench. The attacker must immediately succeed on a DC 14 Constitution saving throw or be poisoned until the start of its next turn.

Behavior & Lore

Nuppeppo roams at night through cemeteries, alleyways, or deserted temple grounds, leaving behind a greasy track.

It neither hunts nor tries to scare travelers. If approached, it just stands there or sluggishly oozes away, ignoring aggression if possible.

When truly threatened, the Nuppeppo uses its Belly Flop or Flabby Slam to push threats aside, then escapes.

Occasional sightings spark rumors of “undying flesh,” but few dare attempt to kill or eat it. Tales abound that those who do soon regret it.

Lore

Fleshy blob-like monster emitting a foul odor, wandering near deserted temples.

ANuppeppo stands out among legendary yokai for its off‑putting appearance and revolting stench. This bizarre entity resembles a mass of living flesh, folded and sagging, with stubby limbs protruding. One might liken it to a soft creature. Its so‑called “eyes,” “nose,” and “mouth” are really just folds of drooping flesh. Yet its most disturbing trait is not its shape at all, but rather the reek of rotting meat it gives off—a stench said to be as foul as a corpse in advanced decay. Its mere presence instills fear, even though it neither attacks nor curses. Some claim it roams the roads at night, but does not vanish come daybreak; others insist it makes a “piko‑piko‑piko” sound with each step.

Despite its nauseating nature, this malodorous yokai conceals a remarkable secret. Rumor has it that devouring its flesh endows one with superhuman strength or even immortality, perhaps depending on the creature’s age or size. Little is known of its origins, and legends remain frustratingly vague as to how it first emerged.

From Yokai Bestiary 5E, p. 78 · Fern Flower Press