A whole bunch of info regarding Willow, now in color! Originally suggested by OnkelInferno & Scrubb!

Willow Wisp

Sentient Fay Creature
Age: Unknown

Physical Characteristics:

The Wisp (the glowy thing):

• Sex: N/A
• Weight: 0.2kg (0.44lbs)
• Volume: 400ml (13.5floz)
• Bright blue glow
• Jelly-like substance
• Resembles a blue flame
• Not alive (or dead)

Despite her looks, she is not a ghost or undead. She's a fay: a creature of magic. She can eat or sleep, but doesn't need it. Her body still feels warm as if alive.

The Body (The physical stuff):

• Sex: Female
• Height: 1.68m (5'6")
• Weight: 120lbs (54.4kg)
• Ghostly White fur
• Glowing Blue eyes
• Black sclera
• Black patterns in fur

The black marks are constantly shifting, albeit very slowly. The more soul she absorbs, the more coated in it she'll become.

Mental Characteristics:

• Lonely
• Good-natured
• Intense feelings of guilt
• Good sense of direction

Willow always knows which way to go, but won't ever tell you! Even drawing a map might not be safe.

Willow's Lantern

Willow's true form is the wisp within her lantern. She can leave it and fly around as the wisp, but it's disorientating for her to move both forms simultaneously.

She can also make the lantern float by lifting it up with her wisp, but moving it this way is harder than just carrying it.

Willow's curse

Willow is cursed to always eventually lead anyone who follows her to their untimely death, typically via accidents. She has no control over this, as it's part of her nature as a will-o-the-wisp.

This was the fate of her first friend, Maya.

While burying her friend, Willow's physical body transformed into a ghostly version of Maya's lioness body, a manifestation Of the guilt she felt.

Willow can travel with someone else without issue, so long as she isn't the one taking the lead. She's always careful that no one directly follows her.

Hollow

So long as Willow's light can reach her body, she can control it. If it's blocked or she moves too far away, her spirit will detach.

While apart, the body will continue to act on "autopilot" but without her mind it's pretty dumb. (or adorably derpy, depending on who you ask)

Some refer to this empty version of Willow's body as "Hollow", To distinguish between them.

Willow rarely leaves her body for long. Doing so will, over time, cause Hollow to develop her own independent personality. At some point she could even become a sentient fay herself, much like Willow did when she originally split from her own "mother."

Alcohol

If willow drinks alcohol, or her wisp form is immersed in it, this can also cause her to temporarily lose Connection to her body.

The Fay Mother

Willow was originally part of a much larger creature. The mother is an ancient, corrupted dragon that spawned all the fay of the wilds for the purpose of collecting souls from lost travelers.

To the mother and the other fay, Willow is considered a malignancy - a single cell of the mother that has stopped serving the rest of the host.