To explain Inada-Kase Boat Ghost in detail:

A variant of the boat ghost that appears with the call of “Inada-kase” along the Fukushima coast. On calm nights, in drifting fog, or before a squall, pale hands and wet sleeves line the gunwale, and a chill voice repeats “lend the inada” from the waves. The inada is a bailer ladle for scooping water from a boat; once lent, the spirit pours seawater back into the craft to sink it. It rarely shows its face head-on, the visage veiled in sea mist, only dripping cuffs and black eyes glinting in the lamp’s edge. Reasonable at heart yet tasked with judging neglect and breaches of maritime order, it favors the sixteenth day of Obon, the dark of the moon, and fishing grounds where memorial rites have lapsed. Traditional countermeasures say to hand over a ladle with its bottom removed; the spirit accepts out of courtesy, but the water spills back to the sea. A pinch of rice ball, hearth ash, or salt-purified rice cake cast with the words “this is an offering” also satisfies its claim. If met with turmoil or shouting, it flies into a rage, unseen hands weighing the oars, dimming the compass, and warping the tide lines. They are a host of the drowned, a balance of the sea, and a mirror of neglected tools and unkept rites. Thus fishers notch their bailer, tie a sprig of shiso or a straw, purify it, and bow to the boat spirit before setting out. Because the ghost returns borrowed tools to the sea, the ladle may wash ashore by morning crusted with salt flowers. On windless nights when the helm grows heavy and water sounds along the side, add no lights, raise no voice, and quietly offer the inada; then the spirit cannot fulfill its debt and slips away in shame.

To explain Murasa (Nigashio-Lodged of Tsuma Village) in detail:

A variant of the funayurei recorded in Tsuma Village, Oki District, Shimane. On nocturnal seas, clusters of faint lights gathering are called Murasa. Locals call the countless drifting sea sparkle nigashio. When that flow blurs into a single round mass that pulses like a pale blue breath, it is feared not as mere sea gleam but as remnants of the drowned lodging in the tide, namely Murasa. It will suddenly gather before a bow to bar the way, dimly lighting the surface and throwing off the sense of course. If a boat rides over it, the light scatters at once to the four directions, shadows on deck and gunwale sway strangely, and though the helm bites, the hull feels as if spinning uselessly on the sea. Not individual ghosts grasping with limbs, but a swarm of lights stroking the hull and upsetting the rhythm of the waves to lure toward grounding, they say. Late at night, when the sea flashes “chik” bright as day for a beat and all falls still, villagers say one is “possessed by Murasa,” stop the rudder, lash a dagger or kitchen knife to a pole, and cut the surface three times. At the sound of blade parting tide, the light thins like unwinding thread and scatters back into ordinary nigashio. Local lore holds that passing a bottomless dipper or throwing rice balls or ash has little effect here, while quietly setting incense flowers or dumplings adrift makes the light keep its circle, skirt the boat, and open a path. Murasa raises no voice, nor demands a bailer. Yet on the sixteenth of Obon the rings double and triple, drawing near and away, harboring an inner dark like a ghost ship’s shadow. Working the sea then is forbidden, for even a veteran skipper is dazzled and drawn to the cape’s black rocks. Its color is cold yet clear, and when met with shouts and disorder it flickers as if with a thin smile. Before those who ravage or foul the sea, the ring narrows and only the water at one’s feet grows unnaturally bright, leaving no escape. Conversely, for those who mourn kin lost at sea and make offerings, it lays a guiding streak in the offshore dark and sets distant whitecaps in relief to lead to safe water veins. Thus Murasa is both a drowning ghost and a guiding ghostlight. On Tsuma’s shore, the custom remains on the first catch night to chant words that calm both sea gods and the dead, then cut the tide with a blade before casting the nets. The light cannot be scooped by hand, nor a voice seized, yet it readily dissolves its form in answer to the threefold cutting rite and quiet offerings, returning to mere nigashio.

To explain Ugume (Kyushu West Coast Variant) in detail:

Across the west coast of Kyushu—especially from Hirado in Nagasaki to Amakusa and Goshoura Island—a variant of the funayurei is known as the Ugume. It appears in night fog or under a windless overcast stillness: an old sailboat with bellied sails despite no wind, or a small unmanned skiff, gliding up silently from behind. Its lights are faint, wavering along the gunwales like something between flame and fireflies. The closer it comes, the farther the sound of waves recedes; though the vessel seems to move forward, the surface of the sea slips backward. This is the sign of possession: cold water seeps into the bilge, oars grow heavy, and the compass drifts a hair off. The Ugume has no fixed form, sometimes turning into the silhouette of an island to lure boats, sometimes showing a non-existent cove offshore to run them aground. From the shadow of a rotted mast it will murmur, “Give me a bilge-scoop,” asking for a scoop or ladle to bail. One must hand over a scoop with a hole in the bottom; give a sound one by mistake and it will pour water over the gunwale without cease, weighing the boat down to sink. In Hirado they say a pinch of ash cast upon the sea will lift the fog. On Goshoura, one calls out “Dropping anchor!” throws a stone first, then casts the anchor—a ritual aligning words and action to tell what lies below, “We intend to stay here,” whereupon the Ugume loosens its hold. A thread of tobacco smoke will also thin it, sending it retreating toward the stern. Offerings include rice balls, rice cakes, and a small amount of ash, and special caution is urged on the sixteenth day of Obon. The Ugume are less indiscriminate vengeful ghosts than a host of those who slipped outside the sea’s order, drawn by lapses in shipboard manners, careless speech, or neglected greetings to the sea gods. If faced squarely, with proper names and rites observed, they slip back into the shadow of the tide. The fear that “it disguises itself as boats or islands” along Kyushu’s west coast reflects memories rooted in fickle currents and tangled shoals—an embodiment of losing one’s way at sea. Ugume also portend maritime misfortune; in fishing villages it is said that on nights they draw near, someone somewhere has lost the path home.

To explain Mouren Yassa, the Vengeful Sea Ghost (Tales of Choshi and Kaijo District) in detail:

A variant of the funayurei remembered along the coast from Choshi City through the old Kaijo District. On stormy nights when fog smothers the sea and whitecaps rise, it approaches from the offshore dark chanting “mōren yassa mōren yassa” in the rhythm of oar beats. The voice rises and falls with wind and current, then stops just beneath the gunwale. A moment later a black dripping arm reaches up from the water and croaks, “Lend a scoop.” Locals gloss mōren as “restless dead,” inaga as “water ladle,” and yassa as the chant for bringing boats in line. When these three arrive together, it portends a surge of drowning souls trying to board. They are a collective of those lost to the sea who have no shore to return to, strongest on the 16th of Obon and on the monthly death-days of the unlaid. Their aim is to sink the boat and add new hands to their wet rail. With the borrowed ladle they tap in seawater, and to the yassa beat they shift the water’s weight toward the bilge until the boat is swallowed. Time-honored countermeasures are set. First, hand over a ladle with the bottom knocked out. Showing a vessel that takes from the sea but not the boat convinces the dead that “water will not enter the hull” and breaks their rhythm. Second, fix them with a stare and hold the boat still. Do not steer, face the wave crests, breathe short, and the swarm loses its heading and melts into the fog. Third, throw ash or rice balls. Ash, as the remnant of shore-fire, points a way home, and rice balls salted for the sea serve as an offering to calm the tide. In Choshi, the one who calls the first haul keeps a guarded tongue, for Mouren Yassa is keen to a skipper’s words. Taboos are strict: putting out to sea on Obon’s 16th, scorning the foghorn and not sounding it, or laughing with the tide-waiting torii at your back will summon them. Their form shifts: they may pace you as a ghost ship under a furled white sail, or press the prow like the shadow of an umibozu. Yet what lingers in the ear is always the beat of “mōren yassa,” and when it fades, the danger passes. Early modern picture books paint them as vengeful spirits, but elder fishers call them “the voice that restates the sea’s law.” If flowers or dumplings are set afloat at the shore, by morning the prow-weed is shed and net frays are stilled. The name later was written as “Fierce Spirits, Eight Calamities,” a dread title of wild might, but at root they are a drifting host. If you hear them offshore, knock out the ladle’s bottom, set your prow straight, and mind your words—that is the shorewise rule kept at Choshi.

To explain Namōrei, Black Little-Craft of Kosode in detail:

A variant of the funayurei from Kosode in Ube Village, Kunohe District, Iwate (now Kosode, Kuji City), whispered locally as the Namōrei. During night squalls or heavy sea fog, a small black-painted boat with a high stern and low prow appears soundlessly, as if running back along a tide line offshore. Its silhouette parts no waves, only blurs the surface like ink, and though no oar or sail is seen, it glides forward. One or several shadowy figures in glossy black garments stand along the gunwale, and only their voices slice through the wind. In a low, lingering tone they demand, “Hand over an oar,” or “Answer,” and if one replies, they at once sheer alongside and seize the other boat’s heading and helm. The Namōrei are the remnants of those who perished at sea and could not return home, craving oars and sculls—the “power to bring one back.” Elders warn that answering opens the mouth of one’s soul, and lending an oar is akin to yielding a boat’s lifeline. Thus in Kosode, when called from the sea at night, one must never respond, but either stand at the rail and glare steadily, or keep one’s hat brim pulled low in silence. The Namōrei are weak to the eye; met with a powerful gaze, they and their black boat melt into the tide fog. If they ask for an oar and are given a bottomless ladle, a split oar, or a holed bamboo scoop—“useless things”—their fixation breaks as seawater spills out at once. This is the widespread funayurei art of “passing the empty,” and along the Tohoku coast, refusing to answer and never handing over anything of substance were especially prized. The black boat appears when the stars hang low, on the sixteenth night of Obon, or when the offshore singing sands cry. White handprints multiplying on the rail and the gunwale growing heavy and low foretell their clinging approach. In contrast, scattering a pinch of rice or ash from one’s palm and sweeping it thrice to sea is said to dissolve the prints into the tide. In Kosode’s rocky coves, sailors shun picking up driftwood oars and loading them, and before setting out they tie a single thread to the oar’s handle to mark a “way home.” The Namōrei are keen to advantage, following slips of speech and bonds of lending to insinuate themselves, so banter and calling across boats are taboo. At a break in the morning fog the black craft vanishes at once, leaving only a chill tang of brine and dark water-spots on the rail. Those who see it refrain from offshore nets that year and offer incense, flowers, and dumplings to the beach deity, as old custom dictates.