Shin

It appears as a slug-like creature, but is neither an animal nor a parasite.↗

The creature's body is translucent, refracting rainbow-like lights inside. Deeper in the light is a soft-bodied creature like a sea anemone, but with human-like hands and feet. It has a head as well, and although it has no face, its head features two antennas that resemble eyes, akin to the head of a slug or the horns of a demon.↗↗

Shin is capable of thought and feeling, and has seemingly been influenced by the people that once worshiped it. It feels no malice or hostility in its own actions, but rather pride in its divine purpose to "guide" humankind. It wants to "save" people as best it can with its ability, and endeavors with resolve to deliver a happy ending for anyone that follows the ritual.↗

However, Shin does not take kindly to resistance, becoming frustrated by Rohan's repeated attempts to stop it and recognizing him as a threat. Shin can be clever in "combat," as it is able to utilize hidden abilities and traps to trick its adversaries into seeing its "holy light." It is often confused by modern technology: for instance, it is unable to distinguish between real people and Polaroid pictures of them.↗↗

Shin can automatically attack at the speed of light, but in order to trigger its attack, a living being must see the light it emits. Once a living being sees Shin's light, it can send signals through their eyes to their brain, trapping them in a deep and eternal sleep with peaceful dreams for the victims to enjoy forevermore.↗

Intangibility

The intruding being of light is impervious to any physical attacks against it, since it is effectively made of light. It surpasses any attacks from Heaven's Door, and can even cast its light through pages created by the Stand.↗

Illusions

Shin casts its own light, tricking the human gaze to see what they want to see, usually in the form of a loved one to help guide the victims to "heaven".↗

Animal Puppeteering

A hidden ability of Shin's: it can cast its light not only into humans, but animals as well. The simpler thought processes of animals allow Shin to manipulate them more easily. It takes control of rats in order to make them aggressively attack Rohan, in a bid to defeat him and "save" his soul.↗